Within 24 h following LPS stimulation there was a striking increase in the levels of c-Rel , p105 , and p50 in the cytosol .

Within 24 h following LPS stimulation there was a striking increase in the levels of <protein>c-Rel</protein> , <protein>p105</protein> , and <protein>p50</protein> in the cytosol .


The increased levels of these proteins correlated with increases in the amounts of their mRNAs during LPS activation of THP-1 cells .

The increased levels of these proteins correlated with increases in the amounts of their <rna>mRNAs</rna> during LPS activation of <cell_line>THP-1 cells</cell_line> .


LPS activation of THP-1 cells resulted in phosphorylation of MAD3 ( an I kappa B -like protein ) , a rapid increase in MAD3 mRNA , and an increase in MAD3 protein by 2 h .

LPS activation of <cell_line>THP-1 cells</cell_line> resulted in phosphorylation of <protein>MAD3</protein> ( an <protein>I kappa B</protein> -like protein ) , a rapid increase in <rna>MAD3 mRNA</rna> , and an increase in <protein>MAD3</protein> protein by 2 h .


Thus , LPS activation of human monocytic cells results in nuclear expression of c-Rel/p50 and p50/p65 ( NF-kappa B ) and induces phosphorylation of MAD3 .

Thus , LPS activation of human <cell_type>monocytic cells</cell_type> results in nuclear expression of <protein>c-Rel/p50</protein> and <protein>p50/p65</protein> ( <protein>NF-kappa B</protein> ) and induces phosphorylation of <protein>MAD3</protein> .


A chimeric type II/type I interleukin-1 receptor can mediate interleukin-1 induction of gene expression in T cells .

A <protein>chimeric type II/type I interleukin-1 receptor</protein> can mediate <protein>interleukin-1</protein> induction of gene expression in <cell_type>T cells</cell_type> .


The type I interleukin-1 receptor ( IL-1R ) is capable of transducing a signal resulting in promoter activation in T cells .

The <protein>type I interleukin-1 receptor</protein> ( <protein>IL-1R</protein> ) is capable of transducing a signal resulting in promoter activation in <cell_type>T cells</cell_type> .


This signal transduction is dependent on the cytoplasmic domain , which consists of 213 amino acids .

This signal transduction is dependent on the <protein>cytoplasmic domain</protein> , which consists of 213 amino acids .


In contrast to the type I receptor , the type II IL-1R has a small cytoplasmic tail , and it is not clear whether this receptor is a signal-transducing or a regulatory molecule .

In contrast to the <protein>type I receptor</protein> , the <protein>type II IL-1R</protein> has a small <protein>cytoplasmic tail</protein> , and it is not clear whether this receptor is a <protein>signal-transducing</protein> or a <protein>regulatory molecule</protein> .


Here we report that the type II IL-1R does not mediate gene activation in Jurkat cells .

Here we report that the <protein>type II IL-1R</protein> does not mediate gene activation in <cell_line>Jurkat cells</cell_line> .


However , a hybrid receptor composed of the extracellular and transmembrane regions of the human type II interleukin-1 fused to the cytoplasmic domain of the human type I IL-1R was capable of transducing a signal across the membrane resulting in a pattern of gene activation identical to that mediated by the type I IL-1R .

However , a hybrid receptor composed of the <protein>extracellular and transmembrane regions</protein> of the <protein>human type II interleukin-1</protein> fused to the <protein>cytoplasmic domain</protein> of the <protein>human type I IL-1R</protein> was capable of transducing a signal across the membrane resulting in a pattern of gene activation identical to that mediated by the <protein>type I IL-1R</protein> .


Our results indicated that the extracellular domain of the type II IL-1R was capable of functionally interacting with interleukin-1 and transmitting the resulting signal to a heterologous cytoplasmic domain .

Our results indicated that the <protein>extracellular domain</protein> of the <protein>type II IL-1R</protein> was capable of functionally interacting with <protein>interleukin-1</protein> and transmitting the resulting signal to a <protein>heterologous cytoplasmic domain</protein> .


A mutation of the glucocorticoid receptor in primary cortisol resistance .

A mutation of the <protein>glucocorticoid receptor</protein> in primary cortisol resistance .


The precise molecular abnormalities that cause primary cortisol resistance have not been completely described .


In a subject with primary cortisol resistance we have observed glucocorticoid receptors ( hGR ) with a decreased affinity for dexamethasone .

In a subject with primary cortisol resistance we have observed <protein>glucocorticoid receptors</protein> ( <protein>hGR</protein> ) with a decreased affinity for dexamethasone .


We hypothesize that a mutation of the hGR glucocorticoid-binding domain is the cause of cortisol resistance .

We hypothesize that a mutation of the <protein>hGR glucocorticoid-binding domain</protein> is the cause of cortisol resistance .


Total RNA isolated from the index subject 's mononuclear leukocytes was used to produce first strand hGR cDNAs , and the entire hGR cDNA was amplified in segments and sequenced .

Total RNA isolated from the index subject 's <cell_type>mononuclear leukocytes</cell_type> was used to produce first strand <dna>hGR cDNAs</dna> , and the entire <dna>hGR cDNA</dna> was amplified in segments and sequenced .


At nucleotide 2 , 317 we identified a homozygous A for G point mutation that predicts an isoleucine ( ATT ) for valine ( GTT ) substitution at amino acid 729 .


When the wild-type hGR and hGR-Ile 729 were expressed in COS-1 cells and assayed for [ 3H ] -Dexamethasone binding , the dissociation constants were 0.799 +/- 0.068 and 1.54 +/- 0.06 nM ( mean +/- SEM ) ( P < 0.01 ) , respectively .

When the <protein>wild-type hGR</protein> and <protein>hGR-Ile 729</protein> were expressed in <cell_line>COS-1 cells</cell_line> and assayed for [ 3H ] -Dexamethasone binding , the dissociation constants were 0.799 +/- 0.068 and 1.54 +/- 0.06 nM ( mean +/- SEM ) ( P < 0.01 ) , respectively .


When the wild-type hGR and hGR-Ile 729 were expressed in CV-1 cells that were cotransfected with the mouse mammary tumor virus long terminal repeat fused to the chloramphenicol acetyl transferase ( CAT ) gene , the hGR-Ile 729 conferred a fourfold decrease in apparent potency on dexamethasone stimulation of CAT activity .

When the <protein>wild-type hGR</protein> and <protein>hGR-Ile 729</protein> were expressed in <cell_line>CV-1 cells</cell_line> that were cotransfected with the <dna>mouse mammary tumor virus long terminal repeat</dna> fused to the <dna>chloramphenicol acetyl transferase ( CAT ) gene</dna> , the <protein>hGR-Ile 729</protein> conferred a fourfold decrease in apparent potency on dexamethasone stimulation of <protein>CAT</protein> activity .


The isoleucine for valine substitution at amino acid 729 impairs the function of the hGR and is the likely cause of primary cortisol resistance in this subject .

The isoleucine for valine substitution at amino acid 729 impairs the function of the <protein>hGR</protein> and is the likely cause of primary cortisol resistance in this subject .


The transcriptionally active factors mediating the effect of the HTLV-I Tax transactivator on the IL-2R alpha kappa B enhancer include the product of the c-rel proto-oncogene .

The <protein>transcriptionally active factors</protein> mediating the effect of the <protein>HTLV-I Tax transactivator</protein> on the <dna>IL-2R alpha kappa B enhancer</dna> include the product of the <dna>c-rel proto-oncogene</dna> .


The transactivator HTLV-I Tax activates the promoter of the gene coding for the interleukin 2 alpha-chain receptor ( IL-2R alpha ) via a kappa B site that can bind several protein species of the rel family .

The transactivator <protein>HTLV-I Tax</protein> activates the <dna>promoter</dna> of the gene coding for the <protein>interleukin 2 alpha-chain receptor</protein> ( <protein>IL-2R alpha</protein> ) via a <dna>kappa B site</dna> that can bind several protein species of the <protein>rel family</protein> .


Tax1 strongly activates the enhancer activity of this motif , in both epithelial HeLa and lymphoid Jurkat cells .

<protein>Tax1</protein> strongly activates the enhancer activity of this motif , in both <cell_line>epithelial HeLa</cell_line> and lymphoid <cell_line>Jurkat cells</cell_line> .


This activation was not observed in undifferentiated embryocarcinoma F9 cells .


Overexpression of the p50 , p65 and Rel proteins in these cells showed that significant activation of the IL-2R alpha kappa B site was observed only with Rel and Rel plus p65 .

Overexpression of the <protein>p50</protein> , <protein>p65</protein> and <protein>Rel proteins</protein> in these cells showed that significant activation of the <protein>IL-2R alpha</protein> <dna>kappa B site</dna> was observed only with <protein>Rel</protein> and <protein>Rel</protein> plus <protein>p65</protein> .


Moreover , whereas both Tax and phorbol 12-myristate 13-acetate ( PMA ) are able to efficiently induce the binding of NF-kappa B to the IL-2R alpha kappa B site , PMA is functionally inactive .

Moreover , whereas both <protein>Tax</protein> and phorbol 12-myristate 13-acetate ( PMA ) are able to efficiently induce the binding of <protein>NF-kappa B</protein> to the <dna>IL-2R alpha kappa B site</dna> , PMA is functionally inactive .


Using the DNA affinity precipitation assay , we observed that Tax1 is able to efficiently induce the binding of Rel , whereas PMA is not .

Using the DNA affinity precipitation assay , we observed that <protein>Tax1</protein> is able to efficiently induce the binding of Rel , whereas PMA is not .


This established a clear difference between both stimuli , indicating that Rel is the functionally active factor .

This established a clear difference between both stimuli , indicating that <protein>Rel</protein> is the <protein>functionally active factor</protein> .


We conclude from these results that the functional activity of members of the rel family is regulated by their interaction with DNA and that Rel can be a potent transcriptional activator on specific kappa B sites .

We conclude from these results that the functional activity of members of the <protein>rel family</protein> is regulated by their interaction with DNA and that <protein>Rel</protein> can be a potent transcriptional activator on specific <dna>kappa B sites</dna> .


Transcriptional regulation of interleukin 3 ( IL3 ) in primary human T lymphocytes .

Transcriptional regulation of <protein>interleukin 3</protein> ( <protein>IL3</protein> ) in <cell_type>primary human T lymphocytes</cell_type> .


Role of AP-1- and octamer-binding proteins in control of IL3 gene expression .

Role of <protein>AP-1- and octamer-binding proteins</protein> in control of <protein>IL3</protein> gene expression .


We have investigated the molecular and biochemical basis for activation of interleukin 3 ( IL3 ) gene expression in primary human T lymphocytes following CD3 and CD2 receptor stimulation or activation by phytohemagglutinin plus phorbol 12-myristate 13-acetate .

We have investigated the molecular and biochemical basis for activation of <protein>interleukin 3</protein> ( <protein>IL3</protein> ) gene expression in <cell_type>primary human T lymphocytes</cell_type> following CD3 and CD2 receptor stimulation or activation by <protein>phytohemagglutinin</protein> plus phorbol 12-myristate 13-acetate .


Using transfection and reporter gene assays specifically designed for primary T lymphocytes in conjunction with gel retardation assays , Western blot analyses and UV cross-linking studies , we found that c-Jun , c-Fos , and octamer-binding proteins play a major role in transcriptional activation of the IL3 gene via their interaction with two specific regions contained within the IL3 5'-flanking sequence .

Using transfection and reporter gene assays specifically designed for <cell_type>primary T lymphocytes</cell_type> in conjunction with gel retardation assays , Western blot analyses and UV cross-linking studies , we found that <protein>c-Jun</protein> , <protein>c-Fos</protein> , and <protein>octamer-binding proteins</protein> play a major role in transcriptional activation of the <dna>IL3 gene</dna> via their interaction with two specific regions contained within the <dna>IL3 5'-flanking sequence</dna> .


Additionally , the region between bases -107 and -59 of the IL3 promoter containing putative AP-2 and Sp1 binding motifs appears necessary for basal level expression of the IL3 gene .

Additionally , the region between bases <dna>-107 and -59</dna> of the <dna>IL3 promoter</dna> containing putative <dna>AP-2 and Sp1 binding motifs</dna> appears necessary for basal level expression of the <protein>IL3</protein> gene .


The data also indicate that CD2 receptor activation and phytohemagglutinin plus phorbol 12-myristate 13-acetate stimulation augment T cell IL3 gene expression through the same cis- and trans-activating signals .

The data also indicate that <protein>CD2</protein> receptor activation and <protein>phytohemagglutinin</protein> plus phorbol 12-myristate 13-acetate stimulation augment T cell <protein>IL3</protein> gene expression through the same cis- and trans-activating signals .


These results should contribute to a better understanding of the regulation of IL3 gene expression in human T lymphocytes .

These results should contribute to a better understanding of the regulation of <protein>IL3</protein> gene expression in <cell_type>human T lymphocytes</cell_type> .


Dimerization of NF-KB2 with RelA ( p65 ) regulates DNA binding , transcriptional activation , and inhibition by an I kappa B-alpha ( MAD-3 ) .

Dimerization of <protein>NF-KB2</protein> with <protein>RelA ( p65 )</protein> regulates DNA binding , transcriptional activation , and inhibition by an <protein>I kappa B-alpha</protein> ( <protein>MAD-3</protein> ) .


Inducible expression of human immunodeficiency virus ( HIV ) is regulated by a cellular transcription factor , nuclear factor kappa B ( NF-kappa B ) .

Inducible expression of human immunodeficiency virus ( HIV ) is regulated by a cellular <protein>transcription factor</protein> , <protein>nuclear factor kappa B</protein> ( <protein>NF-kappa B</protein> ) .


NF-kappa B is composed of distinct subunits ; five independent genes , NFKB1 ( p105 ) , NFKB2 ( p100 ) , RelA ( p65 ) , c-rel and relB , that encode related proteins that bind to kappa B DNA elements have been isolated .

<protein>NF-kappa B</protein> is composed of distinct subunits ; five independent genes , <dna>NFKB1</dna> ( <protein>p105</protein> ) , <dna>NFKB2</dna> ( <protein>p100</protein> ) , <protein>RelA ( p65 )</protein> , <dna>c-rel</dna> and <dna>relB</dna> , that encode related proteins that bind to <dna>kappa B DNA elements</dna> have been isolated .


We have previously found that NFKB2 ( p49/p52 ) acts in concert with RelA ( p65 ) to stimulate the HIV enhancer in Jurkat T-leukemia cells .

We have previously found that <protein>NFKB2 ( p49/p52 )</protein> acts in concert with <protein>RelA ( p65 )</protein> to stimulate the <dna>HIV enhancer</dna> in Jurkat <cell_line>T-leukemia cells</cell_line> .


Here we examine the biochemical basis for the transcriptional regulation of HIV by NFKB2 .

Here we examine the biochemical basis for the transcriptional regulation of HIV by <protein>NFKB2</protein> .


Using Scatchard analysis , we have determined the dissociation constants of homodimeric p49 and heterodimeric p49/p65 for binding to the HIV kappa B site .

Using Scatchard analysis , we have determined the dissociation constants of <protein>homodimeric p49</protein> and <protein>heterodimeric p49/p65</protein> for binding to the <dna>HIV kappa B site</dna> .


p49 has a approximately 18-fold-lower affinity for the HIV kappa B site ( KD = 69.1 pM ) than does the approximately 50-kDa protein NFKB1 ( p50 ) derived from p105 ( KD = 3.9 pM ) .

<protein>p49</protein> has a approximately 18-fold-lower affinity for the HIV <dna>kappa B site</dna> ( KD = 69.1 pM ) than does the approximately 50-kDa protein <protein>NFKB1 ( p50 )</protein> derived from <protein>p105</protein> ( KD = 3.9 pM ) .


In contrast , the affinity of heterodimeric NFKB2 ( p49 ) /RelA ( p65 ) for this site is approximately 6-fold higher ( KD = 11.8 pM ) than that of p49 alone .

In contrast , the affinity of <protein>heterodimeric NFKB2 ( p49 ) /RelA ( p65 )</protein> for this site is approximately 6-fold higher ( KD = 11.8 pM ) than that of <protein>p49</protein> alone .


Consistent with these findings , in vitro transcription was stimulated 18-fold by the addition of preformed , heterodimeric NFKB2 ( p49 ) /RelA ( p65 ) protein .

Consistent with these findings , in vitro transcription was stimulated 18-fold by the addition of preformed , <protein>heterodimeric NFKB2 ( p49 ) /RelA ( p65 ) protein</protein> .


Transcriptional activation of the HIV enhancer was also subject to regulation by recently cloned I kappa B-alpha ( MAD-3 ) .

Transcriptional activation of the HIV enhancer was also subject to regulation by recently cloned <protein>I kappa B-alpha</protein> ( <protein>MAD-3</protein> ) .


Recombinant I kappa B-alpha ( MAD-3 ) inhibited the DNA binding activity of p65 , p49/p65 , and p50/p65 but stimulated the binding of NFKB2 ( p49 ) or NFKB1 ( p50 ) .

Recombinant I kappa B-alpha ( <protein>MAD-3</protein> ) inhibited the DNA binding activity of <protein>p65</protein> , <protein>p49/p65</protein> , and <protein>p50/p65</protein> but stimulated the binding of <protein>NFKB2</protein> ( <protein>p49</protein> ) or NFKB1 ( p50 ) .


Functional activation of an HIV reporter plasmid by p49/p65 in transiently transfected Jurkat T-leukemia cells was also inhibited by coexpression of MAD-3 .

Functional activation of an HIV reporter plasmid by <protein>p49/p65</protein> in <cell_line>transiently transfected Jurkat T-leukemia cells</cell_line> was also inhibited by coexpression of <protein>MAD-3</protein> .


( ABSTRACT TRUNCATED AT 250 WORDS )


The c-rel protooncogene product represses NF-kappa B p65 -mediated transcriptional activation of the long terminal repeat of type 1 human immunodeficiency virus .

The <protein>c-rel protooncogene product</protein> represses <protein>NF-kappa B</protein> <protein>p65</protein> -mediated transcriptional activation of the long terminal repeat of type 1 human immunodeficiency virus .


The long terminal repeat ( LTR ) of the type 1 human immunodeficiency virus ( HIV-1 ) and the 5 ' regulatory region of the gene encoding the interleukin 2 receptor alpha subunit ( IL-2R alpha ) share functional kappa B enhancer elements involved in the regulation of these inducible transcription units during T-cell activation .

The <dna>long terminal repeat</dna> ( <dna>LTR</dna> ) of the type 1 human immunodeficiency virus ( HIV-1 ) and the <dna>5 ' regulatory region</dna> of the gene encoding the <protein>interleukin 2 receptor alpha subunit</protein> ( <protein>IL-2R alpha</protein> ) share functional <dna>kappa B enhancer elements</dna> involved in the regulation of these inducible transcription units during T-cell activation .


These kappa B enhancer elements are recognized by a structurally related family of interactive proteins that includes p50 , p65 , and the product of the c-rel protooncogene ( c-Rel ) .

These <dna>kappa B enhancer elements</dna> are recognized by a structurally related family of interactive proteins that includes <protein>p50</protein> , <protein>p65</protein> , and the product of the <dna>c-rel protooncogene</dna> ( <protein>c-Rel</protein> ) .


Recent biochemical studies have shown that p65 and p50 form the prototypical NF-kappa B complex , which is rapidly translocated from the cytoplasm to the nucleus during T-cell activation .

Recent biochemical studies have shown that <protein>p65</protein> and <protein>p50</protein> form the prototypical <protein>NF-kappa B complex</protein> , which is rapidly translocated from the cytoplasm to the nucleus during T-cell activation .


This intracellular signaling complex potently stimulates kappa B-directed transcription from either the HIV-1 LTR or the IL-2R alpha promoter via the strong transactivation domain present in p65 .

This intracellular signaling complex potently stimulates kappa B-directed transcription from either the <dna>HIV-1 LTR</dna> or the <dna>IL-2R alpha promoter</dna> via the strong transactivation domain present in <protein>p65</protein> .


We now demonstrate that nuclear expression of human c-Rel , which is induced by either phorbol ester or tumor necrosis factor alpha with delayed kinetics relative to p65 , markedly represses p65 -mediated activation of these transcription units .

We now demonstrate that nuclear expression of human <protein>c-Rel</protein> , which is induced by either phorbol ester or <protein>tumor necrosis factor alpha</protein> with delayed kinetics relative to <protein>p65</protein> , markedly represses <protein>p65</protein> -mediated activation of these transcription units .


These inhibitory effects of c-Rel correlate with its DNA-binding activity but not with its ability to heterodimerize with p50 , suggesting that c-Rel inhibition involves competition with p50/p65 for occupancy of the kappa B enhancer element .

These inhibitory effects of <protein>c-Rel</protein> correlate with its DNA-binding activity but not with its ability to heterodimerize with <protein>p50</protein> , suggesting that <protein>c-Rel</protein> inhibition involves competition with <protein>p50/p65</protein> for occupancy of the kappa B enhancer element .


Together , these findings suggest that one function of c-Rel is as a physiologic repressor of the HIV-1 LTR and IL-2R alpha promoters , serving to efficiently counter the strong transcriptional activating effects of p65 .

Together , these findings suggest that one function of <protein>c-Rel</protein> is as a physiologic repressor of the <dna>HIV-1 LTR</dna> and <protein>IL-2R alpha</protein> promoters , serving to efficiently counter the strong transcriptional activating effects of <protein>p65</protein> .


Ras oncogene transformation of human B lymphoblasts is associated with lymphocyte activation and with a block of differentiation .

<dna>Ras oncogene</dna> transformation of <cell_type>human B lymphoblasts</cell_type> is associated with lymphocyte activation and with a block of differentiation .


The p21ras small GTP binding proteins participate in signal transduction from cell surface receptors and affect neoplastic transformation and development in many different cell types .

The <protein>p21ras small GTP binding proteins</protein> participate in signal transduction from cell surface receptors and affect neoplastic transformation and development in many different cell types .


In the present study , we examined the relationship between ras transformation and differentiation of human B lymphocytes .

In the present study , we examined the relationship between ras transformation and differentiation of <cell_type>human B lymphocytes</cell_type> .


We show that the constitutive expression of the T24 Ha-ras oncogene in EBV-immortalized B lymphoblasts was associated with the induction of the interleukin 2 receptor alpha subunit , with an impaired immunoglobulin gene expression , altered adhesion properties and increased survival in serum-free medium .

We show that the constitutive expression of the <dna>T24 Ha-ras oncogene</dna> in <cell_line>EBV-immortalized B lymphoblasts</cell_line> was associated with the induction of the <protein>interleukin 2 receptor alpha subunit</protein> , with an impaired <dna>immunoglobulin gene</dna> expression , altered adhesion properties and increased survival in serum-free medium .


Since induction of the IL-2 receptor alpha subunit is a hallmark of lymphocyte activation , we suggest that p21ras naturally triggers B cell activation .

Since induction of the <protein>IL-2 receptor alpha subunit</protein> is a hallmark of <cell_type>lymphocyte</cell_type> activation , we suggest that <protein>p21ras</protein> naturally triggers <cell_type>B cell</cell_type> activation .


The ras-transformed lymphocytes displayed a fully functional IL-2r , as assessed by c-fos induction following treatment with IL-2 ; nevertheless , they were not growth stimulated by this lymphokine .

The <cell_line>ras-transformed lymphocytes</cell_line> displayed a fully functional <protein>IL-2r</protein> , as assessed by <dna>c-fos</dna> induction following treatment with <protein>IL-2</protein> ; nevertheless , they were not growth stimulated by this <protein>lymphokine</protein> .


The decreased expression of immunoglobulin genes indicates that the ras oncogene blocks terminal differentiation to plasma cells , possibly by inhibiting the activity of lymphocyte-specific transcription factors .

The decreased expression of <dna>immunoglobulin genes</dna> indicates that the <dna>ras oncogene</dna> blocks terminal differentiation to <cell_type>plasma cells</cell_type> , possibly by inhibiting the activity of <protein>lymphocyte-specific transcription factors</protein> .


Somewhat unexpectedly , the constitutive p21ras activity did not cause an increased DNA binding of transcription factors PEA1 ( AP1 ) , PEA3 , Oct-2 or NF-kB

Somewhat unexpectedly , the constitutive <protein>p21ras</protein> activity did not cause an increased DNA binding of <protein>transcription factors</protein> <protein>PEA1</protein> ( <protein>AP1</protein> ) , <protein>PEA3</protein> , <protein>Oct-2</protein> or <protein>NF-kB</protein>


Comparative analysis of NFAT ( nuclear factor of activated T cells ) complex in human T and B lymphocytes .

Comparative analysis of <protein>NFAT</protein> ( <protein>nuclear factor of activated T cells</protein> ) complex in <cell_type>human T and B lymphocytes</cell_type> .


Nuclear factor of activated T cells ( NFAT ) is a transcriptional activator that binds to sequences in the interleukin-2 ( IL-2 ) promoter and is thought to be largely responsible for the T cell-specific inducibility of IL-2 expression .

Nuclear factor of activated T cells ( <protein>NFAT</protein> ) is a <protein>transcriptional activator</protein> that binds to sequences in the <dna>interleukin-2 ( IL-2 ) promoter</dna> and is thought to be largely responsible for the T cell-specific inducibility of <protein>IL-2</protein> expression .


Electrophoretic mobility shift assays ( EMSA ) showed that specific NFAT binding activity could also be induced in human B cells .

Electrophoretic mobility shift assays ( EMSA ) showed that specific <protein>NFAT</protein> binding activity could also be induced in <cell_type>human B cells</cell_type> .


The B cell NFAT complex , however , was not functional , since it failed to activate transcription from an NFAT-driven chloramphenicol acetyltransferase ( CAT ) construct .

The <protein>B cell NFAT complex</protein> , however , was not functional , since it failed to activate transcription from an <dna>NFAT-driven chloramphenicol acetyltransferase ( CAT ) construct</dna> .


Competition with an AP-1 motif or with anti-Jun and anti-Fos antibodies abolished binding to the NFAT motif in both T and B cells , indicating that Jun and Fos are critical for NFAT complex formation in both cell types .

Competition with an <dna>AP-1 motif</dna> or with <protein>anti-Jun</protein> and <protein>anti-Fos antibodies</protein> abolished binding to the <dna>NFAT motif</dna> in both <cell_type>T and B cells</cell_type> , indicating that Jun and Fos are critical for <protein>NFAT complex</protein> formation in both cell types .


Purified recombinant Jun and Fos proteins failed to bind directly to the NFAT motif .

Purified recombinant <protein>Jun and Fos proteins</protein> failed to bind directly to the <dna>NFAT motif</dna> .


However , when combined with unstimulated B or T cell extracts , full-length , but not truncated , Jun/Fos heterodimers were able to form an NFAT complex , indicating the presence of a constitutively expressed nuclear factor ( s ) in B and T cells necessary for the formation of the NFAT complex in both cell types .

However , when combined with unstimulated B or T cell extracts , full-length , but not truncated , Jun/Fos heterodimers were able to form an <protein>NFAT complex</protein> , indicating the presence of a <protein>constitutively expressed nuclear factor</protein> ( s ) in <cell_type>B and T cells</cell_type> necessary for the formation of the <protein>NFAT complex</protein> in both cell types .


An NFAT oligonucleotide carrying mutations in the 5 ' purine-rich part of the NFAT sequence failed to form a complex and to compete with the wild type motif for NFAT complex formation in both T and B cells .

An <protein>NFAT</protein> oligonucleotide carrying mutations in the <dna>5 ' purine-rich part</dna> of the <dna>NFAT sequence</dna> failed to form a complex and to compete with the wild type motif for <protein>NFAT complex</protein> formation in both <cell_type>T and B cells</cell_type> .


We therefore propose a model whereby a core NFAT complex consisting of Jun , Fos , and a constitutive nuclear factor is formed in both T and B cells , but an additional factor and/or post-translational modification of a factor , missing in B cells , might be required for transactivation by NFAT .

We therefore propose a model whereby a core <protein>NFAT complex</protein> consisting of <protein>Jun</protein> , <protein>Fos</protein> , and a <protein>constitutive nuclear factor</protein> is formed in both <cell_type>T and B cells</cell_type> , but an additional factor and/or post-translational modification of a factor , missing in <cell_type>B cells</cell_type> , might be required for transactivation by <protein>NFAT</protein> .


Differential autoregulation of glucocorticoid receptor expression in human T- and B-cell lines .

Differential autoregulation of <protein>glucocorticoid receptor</protein> expression in <cell_line>human T- and B-cell lines</cell_line> .


Regulation of glucocorticoid receptor ( GR ) expression by its cognate ligand was examined in the glucocorticoid-sensitive human leukemic T-cell line 6TG1.1 and in the human B-cell line IM-9 .

Regulation of <protein>glucocorticoid receptor</protein> ( GR ) expression by its cognate ligand was examined in the <cell_line>glucocorticoid-sensitive human leukemic T-cell line 6TG1.1</cell_line> and in the <cell_line>human B-cell line IM-9</cell_line> .


In contrast to the decrease in GR mRNA seen in IM-9 cells after treatment with 1 microM dexamethasone for 16-18 h , treatment of 6TG1.1 cells resulted in an 8-fold increase in GR mRNA , as determined by Northern blot and RNase protection analysis , with a corresponding 3- to 4-fold increase in GR protein .

In contrast to the decrease in <rna>GR mRNA</rna> seen in <cell_line>IM-9 cells</cell_line> after treatment with 1 microM dexamethasone for 16-18 h , treatment of <cell_line>6TG1.1 cells</cell_line> resulted in an 8-fold increase in <rna>GR mRNA</rna> , as determined by Northern blot and <protein>RNase</protein> protection analysis , with a corresponding 3- to 4-fold increase in <protein>GR protein</protein> .


Half-maximal induction of GR mRNA and protein in 6TG1.1 cells was observed between 10-100 nM dexamethasone , and inclusion of 1 microM RU 38486 completely blocked the effects of 100 nM dexamethasone , demonstrating that positive autoregulation of GR expression in 6TG1.1 cells is a receptor-mediated response .

Half-maximal induction of <rna>GR mRNA</rna> and protein in <cell_line>6TG1.1 cells</cell_line> was observed between 10-100 nM dexamethasone , and inclusion of 1 microM RU 38486 completely blocked the effects of 100 nM dexamethasone , demonstrating that positive autoregulation of <protein>GR</protein> expression in <cell_line>6TG1.1 cells</cell_line> is a receptor-mediated response .


Positive autoregulation of GR expression was also observed in glucocorticoid-resistant CEM-C1 cells , which contain functional GR , but whose growth is unaffected by glucocorticoids .

Positive autoregulation of <protein>GR</protein> expression was also observed in <cell_line>glucocorticoid-resistant CEM-C1 cells</cell_line> , which contain functional <protein>GR</protein> , but whose growth is unaffected by glucocorticoids .


Thus , positive autoregulation is neither a consequence nor the sole cause of growth arrest .


The degree of negative autoregulation in IM-9 cells and positive autoregulation in 6TG1.1 cells was unaffected by inhibition of protein synthesis with cycloheximide .

The degree of negative autoregulation in <cell_line>IM-9 cells</cell_line> and positive autoregulation in <cell_line>6TG1.1 cells</cell_line> was unaffected by inhibition of protein synthesis with cycloheximide .


Measurement of GR mRNA turnover in 6TG1.1 cells treated with actinomycin-D revealed a half-life of 2.5 h , which was unaffected by dexamethasone treatment .

Measurement of <rna>GR mRNA</rna> turnover in <cell_line>6TG1.1 cells</cell_line> treated with actinomycin-D revealed a half-life of 2.5 h , which was unaffected by dexamethasone treatment .


A similar half-life was determined in IM-9 cells and was also unaffected by steroid treatment .

A similar half-life was determined in <cell_line>IM-9 cells</cell_line> and was also unaffected by steroid treatment .


These results are consistent with the interpretation that glucocorticoid-mediated autoregulation of GR expression is a tissue-specific primary transcriptional response .


Induction of CD8 antigen and suppressor activity by glucocorticoids in a CEM human leukemic cell clone .

Induction of <protein>CD8 antigen</protein> and suppressor activity by glucocorticoids in a <cell_line>CEM human leukemic cell clone</cell_line> .


The relationship between glucocorticoid effect and regulation of cell surface antigens was investigated in two models of leukemic cell lines , CEM C7 denoted ( r+ , ly+ ) and CEM C1 ( r+ , ly- ) .

The relationship between glucocorticoid effect and regulation of <protein>cell surface antigens</protein> was investigated in two models of <cell_line>leukemic cell lines</cell_line> , <cell_line>CEM C7</cell_line> denoted ( r+ , ly+ ) and <cell_line>CEM C1</cell_line> ( r+ , ly- ) .


The reactivity of murine monoclonal antibodies , anti-CD4-FITC , anti-CD8-FITC , anti-CD2-FITC and anti-calla-FITC , were analyzed using flow cytometry .

The reactivity of <protein>murine monoclonal antibodies</protein> , <protein>anti-CD4-FITC</protein> , <protein>anti-CD8-FITC</protein> , <protein>anti-CD2-FITC</protein> and <protein>anti-calla-FITC</protein> , were analyzed using flow cytometry .


The suppressor function was determined using [ 3H ] thymidine incorporation into phytohemagglutinin-activated peripheral blood lymphocytes .

The suppressor function was determined using [ 3H ] thymidine incorporation into <cell_line>phytohemagglutinin-activated peripheral blood lymphocytes</cell_line> .


Dexamethasone treatment of a human leukemic cell clone CEM C7 caused an increase in a subset of cells expressing the surface antigen CD8 , which is present on suppressor and cytotoxic T-lymphocytes .

Dexamethasone treatment of a <cell_line>human leukemic cell clone CEM C7</cell_line> caused an increase in a subset of cells expressing the <protein>surface antigen CD8</protein> , which is present on suppressor and <cell_type>cytotoxic T-lymphocytes</cell_type> .


By comparison , there was no modification of the expression of CD4 antigen , which is expressed at high levels in these cells .

By comparison , there was no modification of the expression of <protein>CD4 antigen</protein> , which is expressed at high levels in these cells .


After two days of treatment with 5 x 10 ( -8 ) M dexamethasone , CEM C7 cells showed a two-fold increase in suppressor activity compared to untreated cells .

After two days of treatment with 5 x 10 ( -8 ) M dexamethasone , <cell_line>CEM C7 cells</cell_line> showed a two-fold increase in suppressor activity compared to untreated cells .


In contrast , there was no regulation by glucocorticoids of either the CD8 or CD4 antigens in the leukemic clone CEM C1 .

In contrast , there was no regulation by glucocorticoids of either the <protein>CD8</protein> or <protein>CD4 antigens</protein> in the <cell_line>leukemic clone CEM C1</cell_line> .


Furthermore , no modification of the suppressor function in CEM C1 cells by dexamethasone was observed .

Furthermore , no modification of the suppressor function in <cell_line>CEM C1 cells</cell_line> by dexamethasone was observed .


In the human leukemic cells studied here , the ability to induce CD8 antigen expression in a CD4+ cells correlates with the ability to induce cell lysis in a glucocorticoid receptor positive cell population .

In the human leukemic cells studied here , the ability to induce <protein>CD8 antigen</protein> expression in a <cell_line>CD4+ cells</cell_line> correlates with the ability to induce cell lysis in a <cell_line>glucocorticoid receptor positive cell population</cell_line> .


Adenovirus E1A inhibits IFN -induced resistance to cytolysis by natural killer cells .

Adenovirus E1A inhibits <protein>IFN</protein> -induced resistance to cytolysis by <cell_type>natural killer cells</cell_type> .


Infection of target cells with cytopathic viruses inhibits IFN induction of cytolytic resistance to NK cell-mediated cytolysis [ IFN -mediated cytoprotection ( IFN -MCP ) ] .

Infection of <cell_type>target cells</cell_type> with cytopathic viruses inhibits <protein>IFN</protein> induction of cytolytic resistance to NK cell-mediated cytolysis [ <protein>IFN</protein> -mediated cytoprotection ( <protein>IFN</protein> -MCP ) ] .


It has been thought that the virally induced inhibition of IFN -MCP is secondary to the shutdown of cellular macromolecular synthesis that accompanies cytopathic virus infections .

It has been thought that the virally induced inhibition of <protein>IFN</protein> -MCP is secondary to the shutdown of cellular macromolecular synthesis that accompanies cytopathic virus infections .


Group C , adenovirus serotype 5 ( Ad5 ) infection inhibits both IFN -MCP and cellular protein synthesis .

Group C , adenovirus serotype 5 ( Ad5 ) infection inhibits both <protein>IFN</protein> -MCP and <protein>cellular protein</protein> synthesis .


This study determined if the Ad5-induced inhibition of IFN -MCP was independent of adenovirus ( Ad ) infection and secondary only to the expression of the Ad early region 1A gene ( E1A ) .

This study determined if the Ad5-induced inhibition of <protein>IFN</protein> -MCP was independent of adenovirus ( Ad ) infection and secondary only to the expression of the <dna>Ad early region 1A gene</dna> ( <dna>E1A</dna> ) .


To test this hypothesis , 4-h NK cytolysis assays were performed on IFN-gamma-treated human cells infected with an Ad5 E1A deletion mutant , dl343 , or transfected with the Ad5 E1A gene .

To test this hypothesis , 4-h NK cytolysis assays were performed on <cell_line>IFN-gamma-treated human cells</cell_line> infected with an Ad5 <dna>E1A</dna> deletion mutant , dl343 , or transfected with the <dna>Ad5 E1A gene</dna> .


IFN -MCP was not inhibited by infection with dl343 , despite the production of large amounts of both early ( E1B , p55 ) and late ( hexon ) Ad proteins .

<protein>IFN</protein> -MCP was not inhibited by infection with dl343 , despite the production of large amounts of both early ( <protein>E1B</protein> , <protein>p55</protein> ) and late ( <protein>hexon</protein> ) <protein>Ad proteins</protein> .


In contrast to E1A-negative , parental cell lines , IFN -MCP was blocked in Ad5 E1A-transfected epithelial and fibroblastic cell lines .

In contrast to <cell_line>E1A-negative , parental cell lines</cell_line> , <protein>IFN</protein> -MCP was blocked in Ad5 <cell_line>E1A-transfected epithelial</cell_line> and <cell_line>fibroblastic cell lines</cell_line> .


Genetic mapping studies within the E1A gene demonstrated that expression of only the first exon of E1A was sufficient to inhibit IFN -MCP .

Genetic mapping studies within the <dna>E1A gene</dna> demonstrated that expression of only the first exon of <dna>E1A</dna> was sufficient to inhibit <protein>IFN</protein> -MCP .


DNA sequence homology of E1A genes between different Ad groups ( group A , Ad12 ; group C , Ad5 ) is limited almost entirely to three conserved regions located within the first exon of E1A .

DNA sequence homology of <dna>E1A</dna> genes between different Ad groups ( group A , Ad12 ; group C , Ad5 ) is limited almost entirely to three conserved regions located within the first exon of <dna>E1A</dna> .


Because IFN -MCP was also blocked in Ad12 E1A-transfected cell lines , expression of one or more of the E1A-conserved regions may be necessary to inhibit IFN -MCP .

Because <protein>IFN</protein> -MCP was also blocked in <cell_line>Ad12 E1A-transfected cell lines</cell_line> , expression of one or more of the <dna>E1A-conserved regions</dna> may be necessary to inhibit <protein>IFN</protein> -MCP .


In summary , the expression of E1A gene products inhibited IFN -MCP independently of virus infection .

In summary , the expression of <protein>E1A gene products</protein> inhibited <protein>IFN</protein> -MCP independently of virus infection .


E1A 's inhibition of IFN -MCP has the net effect of promoting the selective NK cell-mediated clearance of Ad-infected or Ad-transformed human cells .

<dna>E1A</dna> 's inhibition of <protein>IFN</protein> -MCP has the net effect of promoting the selective NK cell-mediated clearance of Ad-infected or <cell_line>Ad-transformed human cells</cell_line> .


A protein of the AP-1 family is a component of nuclear factor of activated T cells .

A protein of the <protein>AP-1 family</protein> is a component of <protein>nuclear factor of activated T cells</protein> .


Nuclear factor of activated T cells ( NF-AT ) is a transcriptional activator involved in the induction of IL-2 gene expression .

<protein>Nuclear factor of activated T cells</protein> ( <protein>NF-AT</protein> ) is a <protein>transcriptional activator</protein> involved in the induction of <protein>IL-2</protein> gene expression .


The response element for NF-AT is a sequence localized between -285/-254 in the IL-2 regulatory region .

The response element for <protein>NF-AT</protein> is a sequence localized between <dna>-285/-254</dna> in the <dna>IL-2 regulatory region</dna> .


The composition of NF-AT protein is still not fully elucidated .

The composition of <protein>NF-AT</protein> protein is still not fully elucidated .


We demonstrate that , in normal human T cells , an AP-1 protein is a component of the NF-AT protein complex .

We demonstrate that , in normal human <cell_type>T cells</cell_type> , an <protein>AP-1 protein</protein> is a component of the <protein>NF-AT protein complex</protein> .


This was evidenced by the ability of the AP-1 site to compete with the NF-AT site for binding to NF-AT and by the capacity of immobilized anti-Jun and anti-Fos antibodies to deplete NF-AT -binding activity from nuclear extracts of activated T cells .

This was evidenced by the ability of the <dna>AP-1 site</dna> to compete with the <protein>NF-AT</protein> site for binding to <protein>NF-AT</protein> and by the capacity of <protein>immobilized anti-Jun</protein> and <protein>anti-Fos</protein> antibodies to deplete <protein>NF-AT</protein> -binding activity from nuclear extracts of <cell_type>activated T cells</cell_type> .


There was no detectable binding of in vitro translated Jun/Fos heterodimer ( AP-1 ) to the NF-AT sequence , and the NF-AT sequence was unable to inhibit the binding of Jun/Fos to the AP-1 sequence .

There was no detectable binding of in vitro translated <protein>Jun/Fos heterodimer</protein> ( <protein>AP-1</protein> ) to the <protein>NF-AT</protein> sequence , and the <dna>NF-AT sequence</dna> was unable to inhibit the binding of <protein>Jun/Fos</protein> to the <dna>AP-1 sequence</dna> .


The presence of an AP-1 protein in the NF-AT protein complex may regulate NF-AT -binding activity through protein-protein interaction .

The presence of an <protein>AP-1</protein> protein in the <protein>NF-AT</protein> protein complex may regulate <protein>NF-AT</protein> -binding activity through protein-protein interaction .


Interaction between NF-kappa B -and serum response factor -binding elements activates an interleukin-2 receptor alpha-chain enhancer specifically in T lymphocytes .

Interaction between <protein>NF-kappa B</protein> -and <protein>serum response factor</protein> -binding elements activates an <dna>interleukin-2 receptor alpha-chain enhancer</dna> specifically in <cell_type>T lymphocytes</cell_type> .


We find that a short enhancer element containing the NF-kappa B binding site from the interleukin-2 receptor alpha-chain gene ( IL-2R alpha ) is preferentially activated in T cells .

We find that a short enhancer element containing the <dna>NF-kappa B binding site</dna> from the <dna>interleukin-2 receptor alpha-chain gene</dna> ( <protein>IL-2R alpha</protein> ) is preferentially activated in <cell_type>T cells</cell_type> .


The IL-2R alpha enhancer binds NF-kappa B poorly and is only weakly activated by the NF-kappa B site alone .

The <protein>IL-2R alpha</protein> enhancer binds <protein>NF-kappa B</protein> poorly and is only weakly activated by the <dna>NF-kappa B site</dna> alone .


Serum response factor ( SRF ) binds to a site adjacent to the NF-kappa B site in the IL-2R enhancer , and both sites together have strong transcriptional activity specifically in T cells .

<protein>Serum response factor</protein> ( <protein>SRF</protein> ) binds to a site adjacent to the <dna>NF-kappa B site</dna> in the <dna>IL-2R enhancer</dna> , and both sites together have strong transcriptional activity specifically in <cell_type>T cells</cell_type> .


Surprisingly , the levels of SRF constitutively expressed in T cells are consistently higher than in other cell types .

Surprisingly , the levels of <protein>SRF</protein> constitutively expressed in <cell_type>T cells</cell_type> are consistently higher than in other cell types .


Overexpression of SRF in B cells causes the IL-2R enhancer to function as well as it does in T cells , suggesting that the high level of SRF binding in T cells is functionally important .

Overexpression of <protein>SRF</protein> in <cell_type>B cells</cell_type> causes the <dna>IL-2R enhancer</dna> to function as well as it does in <cell_type>T cells</cell_type> , suggesting that the high level of <protein>SRF</protein> binding in <cell_type>T cells</cell_type> is functionally important .


Mutual regulation of the transcriptional activator NF-kappa B and its inhibitor , I kappa B-alpha .

Mutual regulation of the <protein>transcriptional activator</protein> <protein>NF-kappa B</protein> and its inhibitor , <protein>I kappa B-alpha</protein> .


The NK-kappa B transcription factor complex is sequestered in the cytoplasm by the inhibitory protein I kappa B-alpha ( MAD-3 ) .

The <protein>NK-kappa B transcription factor complex</protein> is sequestered in the cytoplasm by the inhibitory protein <protein>I kappa B-alpha</protein> ( <protein>MAD-3</protein> ) .


Various cellular stimuli relieve this inhibition by mechanisms largely unknown , leading to NF-kappa B nuclear localization and transactivation of its target genes .

Various cellular stimuli relieve this inhibition by mechanisms largely unknown , leading to <protein>NF-kappa B</protein> nuclear localization and transactivation of its target genes .


It is demonstrated here with human T lymphocytes and monocytes that different stimuli , including tumor necrosis factor alpha and phorbol 12-myristate 13-acetate , cause rapid degradation of I kappa B-alpha , with concomitant activation of NF-kappa B , followed by a dramatic increase in I kappa B-alpha mRNA and protein synthesis .

It is demonstrated here with <cell_type>human T lymphocytes</cell_type> and <cell_type>monocytes</cell_type> that different stimuli , including <protein>tumor necrosis factor alpha</protein> and phorbol 12-myristate 13-acetate , cause rapid degradation of <protein>I kappa B-alpha</protein> , with concomitant activation of <protein>NF-kappa B</protein> , followed by a dramatic increase in <rna>I kappa B-alpha mRNA</rna> and protein synthesis .


Transfection studies reveal that the I kappa B-alpha mRNA and the encoded protein are potently induced by NF-kappa B and by homodimers of p65 and of c-Rel .

Transfection studies reveal that the <rna>I kappa B-alpha mRNA</rna> and the encoded protein are potently induced by <protein>NF-kappa B</protein> and by homodimers of <protein>p65</protein> and of <protein>c-Rel</protein> .


We propose a model in which NF-kappa B and I kappa B-alpha mutually regulate each other in a cycle : saturating amounts of the inhibitory I kappa B-alpha protein are destroyed upon stimulation , allowing rapid activation of NF-kappa B .

We propose a model in which <protein>NF-kappa B</protein> and <protein>I kappa B-alpha</protein> mutually regulate each other in a cycle : saturating amounts of the inhibitory <protein>I kappa B-alpha</protein> protein are destroyed upon stimulation , allowing rapid activation of <protein>NF-kappa B</protein> .


Subsequently , I kappa B-alpha mRNA and protein levels are quickly induced by the activated NF-kappa B .

Subsequently , <rna>I kappa B-alpha mRNA</rna> and protein levels are quickly induced by the activated <protein>NF-kappa B</protein> .


This resurgence of I kappa B-alpha protein acts to restore an equilibrium in which NF-kappa B is again inhibited .

This resurgence of <protein>I kappa B-alpha</protein> protein acts to restore an equilibrium in which <protein>NF-kappa B</protein> is again inhibited .


Replication of type 1 human immunodeficiency viruses containing linker substitution mutations in the -201 to -130 region of the long terminal repeat .

Replication of type 1 human immunodeficiency viruses containing linker substitution mutations in the <dna>-201 to -130 region</dna> of the <dna>long terminal repeat</dna> .


In previous transfection analyses using the chloramphenicol acetyltransferase reporter gene system , we determined that linker substitution ( LS ) mutations between -201 and -130 ( relative to the transcription start site ) of the human immunodeficiency virus type 1 long terminal repeat ( LTR ) caused moderate decreases in LTR transcriptional activity in a T-cell line ( S.L.Zeichner , J.Y.H. Kim , and J.C.Alwine , J.Virol.65 : 2436-2444 , 1991 ) .

In previous transfection analyses using the <protein>chloramphenicol acetyltransferase</protein> <dna>reporter gene</dna> system , we determined that linker substitution ( LS ) mutations between <dna>-201 and -130</dna> ( relative to the transcription start site ) of the human immunodeficiency virus type 1 <dna>long terminal repeat</dna> ( <dna>LTR</dna> ) caused moderate decreases in <dna>LTR</dna> transcriptional activity in a <cell_line>T-cell line</cell_line> ( S.L.Zeichner , J.Y.H. Kim , and J.C.Alwine , J.Virol.65 : 2436-2444 , 1991 ) .


In order to confirm the significance of this region in the context of viral replication , we constructed several of these LS mutations ( -201 to - 184 , -183 to -166 , -165 to -148 , and -148 to -130 ) in proviruses and prepared viral stocks by cocultivation of transfected RD cells with CEMx174 cells .

In order to confirm the significance of this region in the context of viral replication , we constructed several of these LS mutations ( <dna>-201 to - 184</dna> , <dna>-183 to -166</dna> , <dna>-165 to -148</dna> , and <dna>-148 to -130</dna> ) in proviruses and prepared viral stocks by cocultivation of <cell_line>transfected RD cells</cell_line> with <cell_line>CEMx174 cells</cell_line> .


In addition , two mutations between -93 and -76 and between -75 and -58 were utilized , since they affect the nuclear factor kappa B ( NF-kappa B ) - and Sp1-binding sites and were expected to diminish viral replication .

In addition , two mutations between <dna>-93 and -76</dna> and between <dna>-75 and -58</dna> were utilized , since they affect the <dna>nuclear factor kappa B ( NF-kappa B ) - and Sp1-binding sites</dna> and were expected to diminish viral replication .


Our results suggest that while transfection analyses offer an adequate approximation of the effects of the LS mutations , the analysis of viral replication using a mutant viral stock presents a more accurate picture , which is sometimes at variance with the transfection results .


Three mutants ( -201/-184 NXS , -165/-148 NXS , and -147/-130 NXS ) had effects on viral replication that were much more severe than the effects predicted from their performance in transfection analyses , and the effects of two LS mutations ( -201/-184 NXS and -183/-166 NXS ) were not predicted by their effects in transfection .


In addition , we observed cell type-specific permissiveness to replication of some mutant viruses .


In the cell types tested , the LS mutations indicated an apparent requirement not only for the intact NF-kappa B and SP1-binding sites but also for several regions between -201 and -130 not previously associated with viral infectivity .

In the cell types tested , the LS mutations indicated an apparent requirement not only for the intact <protein>NF-kappa B</protein> and <dna>SP1-binding sites</dna> but also for several regions between <dna>-201 and -130</dna> not previously associated with viral infectivity .


Transcription factor GATA-1 and erythroid development .

<protein>Transcription factor</protein> <protein>GATA-1</protein> and erythroid development .


In summary , we derived an experimental system that allows us to dissect the function of GATA-1 in red cell development at a genetic level .

In summary , we derived an experimental system that allows us to dissect the function of <protein>GATA-1</protein> in <cell_type>red cell</cell_type> development at a genetic level .


We have established the essential nature of GATA-1 during both primitive and definitive erythropoiesis .

We have established the essential nature of <protein>GATA-1</protein> during both primitive and definitive erythropoiesis .


By ablating the expression of the endogenous GATA-1 gene , we are in a position to introduce a variety of constructs that harbor subtle modifications in flanking or protein-coding sequences .

By ablating the expression of the endogenous <dna>GATA-1 gene</dna> , we are in a position to introduce a variety of constructs that harbor subtle modifications in flanking or <dna>protein-coding sequences</dna> .


We can now study regulatory regions and functional domains of the protein in the context of a true erythroid environment , experiments that have not been possible heretofore .


Although the assay involves the dramatic loss of red cell production , it should be possible to define important regulatory domains that can then be assayed using less stringent systems , such as cell-free extracts for in vitro transcription .


The ideal situation would be analyses conducted in GATA-1 -erythroid cells .

The ideal situation would be analyses conducted in <cell_line>GATA-1 -erythroid cells</cell_line> .


However , these cells have been impossible to generate given the requirement of GATA-1 for Epo receptor expression and red cell viability ( C. Simon and S. Orkin , unpublished observations ) .

However , these cells have been impossible to generate given the requirement of <protein>GATA-1</protein> for <protein>Epo receptor</protein> expression and <cell_type>red cell</cell_type> viability ( C. Simon and S. Orkin , unpublished observations ) .


It may be possible to produce such cells by first expressing the Epo receptor under the influence of a constitutive promoter and then targeting the GATA-1 gene .

It may be possible to produce such cells by first expressing the <protein>Epo receptor</protein> under the influence of a constitutive promoter and then targeting the <dna>GATA-1 gene</dna> .


If GATA-1 -red cells were available , the analyses would involve the actual transcription of or chromatin structure surrounding the globin genes .

If <cell_line>GATA-1 -red cells</cell_line> were available , the analyses would involve the actual transcription of or chromatin structure surrounding the <dna>globin genes</dna> .


Structure-function studies of the GATA-1 protein could be greatly simplified and a larger number of mutants studied .

Structure-function studies of the <protein>GATA-1</protein> protein could be greatly simplified and a larger number of mutants studied .


However , the ES cell system can be used as an alternative until targeted erythroleukemia cells become available .

However , the ES cell system can be used as an alternative until <cell_line>targeted erythroleukemia cells</cell_line> become available .


Other applications involve the introduction of other GATA-binding protein family members to determine whether they rescue the mutation .

Other applications involve the introduction of other <protein>GATA-binding protein family members</protein> to determine whether they rescue the mutation .


If they can not , chimeric proteins can be tested to identify which amino acids distinguish the different family members .

If they can not , <protein>chimeric proteins</protein> can be tested to identify which amino acids distinguish the different family members .


We feel that these experiments are vital to understanding the function of GATA-1 during erythroid ontogeny .

We feel that these experiments are vital to understanding the function of <protein>GATA-1</protein> during erythroid ontogeny .


How does GATA-1 regulate red cell genes like globin or the Epo receptor ? Once we identify the functional domains of the GATA-binding proteins , we hope to learn what proteins GATA-1 binds to in the basic transcription machinery or in chromatin .

How does <protein>GATA-1</protein> regulate <dna>red cell genes</dna> like <dna>globin</dna> or the <protein>Epo receptor</protein> ? Once we identify the functional domains of the <protein>GATA-binding proteins</protein> , we hope to learn what proteins <protein>GATA-1</protein> binds to in the basic transcription machinery or in chromatin .


Is GATA-1 necessary for globin gene switching ? GATA-1 may be modified differently during development so that the locus control region can interact with different globin promoters .

Is <protein>GATA-1</protein> necessary for globin gene switching ? <protein>GATA-1</protein> may be modified differently during development so that the locus control region can interact with different <dna>globin promoters</dna> .


We may find that one region of the protein is required for embryonic expression and another for adult globin gene expression .

We may find that one region of the protein is required for embryonic expression and another for adult <dna>globin gene</dna> expression .


A human putative lymphocyte G0/G1 switch gene homologous to a rodent gene encoding a zinc-binding potential transcription factor .

A <dna>human putative lymphocyte G0/G1 switch gene</dna> homologous to a <dna>rodent gene</dna> encoding a <protein>zinc-binding potential transcription factor</protein> .


G0S24 is a member of a set of genes ( putative G0/G1 switch regulatory genes ) that are expressed transiently within 1-2 hr of the addition of lectin or cycloheximide to human blood mononuclear cells .

<dna>G0S24</dna> is a member of a set of genes ( <dna>putative G0/G1 switch regulatory genes</dna> ) that are expressed transiently within 1-2 hr of the addition of <protein>lectin</protein> or cycloheximide to <cell_type>human blood mononuclear cells</cell_type> .


Comparison of a full-length cDNA sequence with the corresponding genomic sequence reveals an open reading frame of 326 amino acids , distributed across two exons .

Comparison of a <dna>full-length cDNA sequence</dna> with the corresponding genomic sequence reveals an <dna>open reading frame</dna> of 326 amino acids , distributed across two <dna>exons</dna> .


Potential phosphorylation sites include the sequence PSPTSPT , which resembles an RNA polymerase II repeat reported to be a target of the cell cycle control kinase cdc2 .

Potential <protein>phosphorylation sites</protein> include the sequence <protein>PSPTSPT</protein> , which resembles an <protein>RNA polymerase II repeat</protein> reported to be a target of the <protein>cell cycle control kinase cdc2</protein> .


Comparison of the derived protein sequence with those of rodent homologs allows classification into three groups .


Group 1 contains G0S24 and the rat and mouse TIS11 genes ( also known as TTP , Nup475 , and Zfp36 ) .

Group 1 contains <dna>G0S24</dna> and the <dna>rat and mouse TIS11 genes</dna> ( also known as <dna>TTP</dna> , <dna>Nup475</dna> , and <dna>Zfp36</dna> ) .


Members of this group have three tetraproline repeats .

Members of this group have <protein>three tetraproline repeats</protein> .


Groups 1 and 2 have a serine-rich region and an `` arginine element `` ( RRLPIF ) at the carboxyl terminus .

Groups 1 and 2 have a <protein>serine-rich region</protein> and an `` <protein>arginine element</protein> `` ( <protein>RRLPIF</protein> ) at the <protein>carboxyl terminus</protein> .


All groups contain cysteine- and histidine-rich putative zinc finger domains and a serine-phenylalanine `` SFS '' domain similar to part of the large subunit of eukaryotic RNA polymerase II .

All groups contain <protein>cysteine- and histidine-rich putative zinc finger domains</protein> and a <protein>serine-phenylalanine `` SFS '' domain</protein> similar to part of the large subunit of <protein>eukaryotic RNA polymerase II</protein> .


Comparison of group 1 human and mouse genomic sequences shows high conservation in the 5 ' flank and exons .

Comparison of group 1 <dna>human and mouse genomic sequences</dna> shows high conservation in the <dna>5 ' flank</dna> and <dna>exons</dna> .


A CpG island suggests expression in the germ line .


G0S24 has potential sites for transcription factors in the 5 ' flank and intron ; these include a serum response element .

<dna>G0S24</dna> has potential sites for <protein>transcription factors</protein> in the <dna>5 ' flank</dna> and <dna>intron</dna> ; these include a <dna>serum response element</dna> .


Protein and genomic sequences show similarities with those of a variety of proteins involved in transcription , suggesting that the G0S24 product has a similar role .

Protein and genomic sequences show similarities with those of a variety of proteins involved in transcription , suggesting that the <protein>G0S24 product</protein> has a similar role .


Regulation of lymphoid-specific immunoglobulin mu heavy chain gene enhancer by ETS-domain proteins .

Regulation of <dna>lymphoid-specific immunoglobulin mu heavy chain gene enhancer</dna> by ETS-domain proteins .


The enhancer for the immunoglobulin mu heavy chain gene ( IgH ) activates a heterologous gene at the pre-B cell stage of B lymphocyte differentiation .

The <dna>enhancer</dna> for the <dna>immunoglobulin mu heavy chain gene</dna> ( <protein>IgH</protein> ) activates a <dna>heterologous gene</dna> at the pre-B cell stage of <cell_type>B lymphocyte</cell_type> differentiation .


A lymphoid-specific element , microB , is necessary for enhancer function in pre-B cells .

A <dna>lymphoid-specific element</dna> , <dna>microB</dna> , is necessary for <dna>enhancer</dna> function in <cell_type>pre-B cells</cell_type> .


A microB binding protein is encoded by the PU.1/Spi-1 proto-oncogene .

A <protein>microB binding protein</protein> is encoded by the <dna>PU.1/Spi-1 proto-oncogene</dna> .


Another sequence element , microA , was identified in the mu enhancer that binds the product of the ets-1 proto-oncogene .

Another <dna>sequence element</dna> , <dna>microA</dna> , was identified in the <dna>mu enhancer</dna> that binds the product of the <dna>ets-1 proto-oncogene</dna> .


The microA motif was required for microB-dependent enhancer activity , which suggests that a minimal B cell-specific enhancer is composed of both the PU.1 and Ets-1 binding sites .

The <dna>microA</dna> motif was required for <dna>microB-dependent enhancer</dna> activity , which suggests that a <dna>minimal B cell-specific enhancer</dna> is composed of both the <dna>PU.1 and Ets-1 binding sites</dna> .


Co-expression of both PU.1 and Ets-1 in nonlymphoid cells trans-activated reporter plasmids that contained the minimal mu enhancer .

Co-expression of both <protein>PU.1</protein> and <protein>Ets-1</protein> in <cell_type>nonlymphoid cells</cell_type> <dna>trans-activated reporter plasmids</dna> that contained the minimal <dna>mu enhancer</dna> .


These results implicate two members of the Ets family in the activation of IgH gene expression .

These results implicate two members of the <protein>Ets family</protein> in the activation of <dna>IgH gene</dna> expression .


1 , 25-Dihydroxy vitamin D3 and 12-O-tetradecanoyl phorbol-13-acetate synergistically induce monocytic cell differentiation : FOS and RB expression .

1 , 25-Dihydroxy vitamin D3 and 12-O-tetradecanoyl phorbol-13-acetate synergistically induce <cell_type>monocytic cell</cell_type> differentiation : <protein>FOS</protein> and <protein>RB</protein> expression .


1 , 25-dihydroxy vitamin D3 and 12-O-tetradecanoyl phorbol-13-acetate ( TPA ) interact synergistically to induce monocytic differentiation of U937 histiocytic lymphoma cells .

1 , 25-dihydroxy vitamin D3 and 12-O-tetradecanoyl phorbol-13-acetate ( TPA ) interact synergistically to induce monocytic differentiation of <cell_line>U937 histiocytic lymphoma cells</cell_line> .


Addition of TPA causes an otherwise ineffective dose of 1 , 25-dihydroxy vitamin D3 to induce differentiation .


The induced differentiation depends on the simultaneous ( vs. sequential ) presence of both agents .


The kinetics of induced differentiation are consistent with a G1 specific cellular response to initiate the metabolic cascade culminating in cell differentiation .


The induced differentiation occurs with down-regulation of c-fos protein and an accompanying up-regulation of RB protein expression , consistent with a possible need for up-regulated RB expression to maintain a given differentiated phenotype and suppress transcriptional activators that might typically be associated with proliferation .

The induced differentiation occurs with down-regulation of <protein>c-fos protein</protein> and an accompanying up-regulation of <protein>RB protein</protein> expression , consistent with a possible need for up-regulated <protein>RB</protein> expression to maintain a given differentiated phenotype and suppress <protein>transcriptional activators</protein> that might typically be associated with proliferation .


Ectopic expression of a conditional GATA-2/estrogen receptor chimera arrests erythroid differentiation in a hormone-dependent manner .

Ectopic expression of a conditional <protein>GATA-2/estrogen receptor chimera</protein> arrests erythroid differentiation in a hormone-dependent manner .


The GATA factors are a family of transcriptional regulatory proteins in eukaryotes that share extensive homology in their DNA-binding domains .

The <protein>GATA factors</protein> are a family of <protein>transcriptional regulatory proteins</protein> in eukaryotes that share extensive homology in their <protein>DNA-binding domains</protein> .


One enigmatic aspect of GATA factor expression is that several GATA proteins , which ostensibly share the same DNA-binding site specificity , are coexpressed in erythroid cells .

One enigmatic aspect of <protein>GATA factor</protein> expression is that several <protein>GATA proteins</protein> , which ostensibly share the same <protein>DNA-binding site</protein> specificity , are coexpressed in erythroid cells .


To elucidate the roles of individual GATA factors in erythropoiesis , conditional alleles of GATA-1 , GATA-2 , and GATA-3 were prepared by fusing each of the factors to the hormone-binding domain of the human estrogen receptor ( ER ) .

To elucidate the roles of individual <protein>GATA factors</protein> in erythropoiesis , conditional alleles of <protein>GATA-1</protein> , <protein>GATA-2</protein> , and <protein>GATA-3</protein> were prepared by fusing each of the factors to the <protein>hormone-binding domain</protein> of the <protein>human estrogen receptor</protein> ( <protein>ER</protein> ) .


These GATA/ER chimeric factors were shown to be hormone-inducible trans-activating proteins in transient transfection assays .

These <protein>GATA/ER chimeric factors</protein> were shown to be <protein>hormone-inducible trans-activating proteins</protein> in transient transfection assays .


When stably introduced into primary erythroblasts or conditionally transformed erythroid progenitors cells , exogenous GATA-2/ER promoted proliferation and inhibited terminal differentiation in an estrogen-dependent manner .

When stably introduced into <cell_type>primary erythroblasts</cell_type> or <cell_line>conditionally transformed erythroid progenitors cells</cell_line> , exogenous <protein>GATA-2/ER</protein> promoted proliferation and inhibited terminal differentiation in an estrogen-dependent manner .


These phenotypic effects are specifically attributable to the action of ectopically expressed GATA-2/ER because erythroblasts expressing exogenous GATA-2 are constitutively arrested in differentiation and because erythroid progenitors expressing either Gal/ER or GATA-3/ER do not display a hormone-responsive block in differentiation .

These phenotypic effects are specifically attributable to the action of ectopically expressed <protein>GATA-2/ER</protein> because erythroblasts expressing exogenous <protein>GATA-2</protein> are constitutively arrested in differentiation and because <cell_line>erythroid progenitors</cell_line> expressing either <protein>Gal/ER</protein> or <protein>GATA-3/ER</protein> do not display a hormone-responsive block in differentiation .


Thus , the GATA-2 transcription factor appears to play a role in regulating the self-renewal capacity of early erythroid progenitor cells .

Thus , the <protein>GATA-2 transcription factor</protein> appears to play a role in regulating the self-renewal capacity of <cell_type>early erythroid progenitor cells</cell_type> .


Mice deficient for the 55 kd tumor necrosis factor receptor are resistant to endotoxic shock , yet succumb to L. monocytogenes infection .

Mice deficient for the <protein>55 kd tumor necrosis factor receptor</protein> are resistant to endotoxic shock , yet succumb to L. monocytogenes infection .


The multiple biological activities of tumor necrosis factor ( TNF ) are mediated by two distinct cell surface receptors of 55 kd ( TNFRp55 ) and 75 kd ( TNFRp75 ) .

The multiple biological activities of <protein>tumor necrosis factor</protein> ( <protein>TNF</protein> ) are mediated by two distinct <protein>cell surface receptors</protein> of <protein>55 kd</protein> ( <protein>TNFRp55</protein> ) and <protein>75 kd</protein> ( <protein>TNFRp75</protein> ) .


Using gene targeting , we generated a TNFRp55 -deficient mouse strain .

Using gene targeting , we generated a <protein>TNFRp55</protein> -deficient mouse strain .


Cells from TNFRp55-/-mutant mice lack expression of TNFRp55 but display normal numbers of high affinity TNFRp75 molecules .

Cells from TNFRp55-/-mutant mice lack expression of <protein>TNFRp55</protein> but display normal numbers of <protein>high affinity TNFRp75 molecules</protein> .


Thymocyte development and lymphocyte populations are unaltered , and clonal deletion of potentially self-reactive T cells is not impaired .

<cell_type>Thymocyte</cell_type> development and <cell_type>lymphocyte populations</cell_type> are unaltered , and clonal deletion of potentially <cell_type>self-reactive T cells</cell_type> is not impaired .


However , TNF signaling is largely abolished , as judged by the failure of TNF to induce NF-kappa B in T lymphocytes from TNFRp55 -deficient mice .

However , <protein>TNF</protein> signaling is largely abolished , as judged by the failure of <protein>TNF</protein> to induce <protein>NF-kappa B</protein> in <cell_type>T lymphocytes</cell_type> from <protein>TNFRp55</protein> -deficient mice .


The loss of TNFRp55 function renders mice resistant to lethal dosages of either lipopolysaccharides or S. aureus enterotoxin B .

The loss of <protein>TNFRp55</protein> function renders mice resistant to lethal dosages of either lipopolysaccharides or <protein>S. aureus enterotoxin B</protein> .


In contrast , TNFRp55-deficient mice are severely impaired to clear L. monocytogenes and readily succumb to infection .


Thus , the 55 kd TNFR plays a decisive role in the host 's defense against microorganisms and their pathogenic factors .

Thus , the <protein>55 kd TNFR</protein> plays a decisive role in the host 's defense against microorganisms and their pathogenic factors .


Costimulation of peripheral blood T cell activation by human endothelial cells .

Costimulation of <cell_type>peripheral blood T cell</cell_type> activation by <cell_type>human endothelial cells</cell_type> .


Enhanced IL-2 transcription correlates with increased c-fos synthesis and increased Fos content of AP-1 .

Enhanced <protein>IL-2</protein> transcription correlates with increased <protein>c-fos</protein> synthesis and increased <protein>Fos</protein> content of <protein>AP-1</protein> .


Endothelial cells ( EC ) act as APC for resting PBL in vitro , and may have important roles in vivo in the pathogenesis of allograft rejection and delayed hypersensitivity .

<cell_type>Endothelial cells</cell_type> ( <cell_type>EC</cell_type> ) act as APC for <cell_type>resting PBL</cell_type> in vitro , and may have important roles in vivo in the pathogenesis of allograft rejection and delayed hypersensitivity .


We previously reported that human umbilical vein EC provide costimulatory signals to PHA-stimulated PBL via CD2 : lymphocyte function-associated Ag-3 and an unidentified ligand pair , resulting in a three- to eight-fold enhancement of IL-2 production .

We previously reported that <cell_type>human umbilical vein EC</cell_type> provide costimulatory signals to <cell_type>PHA-stimulated PBL</cell_type> via <protein>CD2 : lymphocyte function-associated Ag-3</protein> and an unidentified ligand pair , resulting in a three- to eight-fold enhancement of <protein>IL-2</protein> production .


The physiologic relevance of this increase was demonstrated by the proliferative advantage provided by EC to PBL suboptimally stimulated with mAb OKT3 .

The physiologic relevance of this increase was demonstrated by the proliferative advantage provided by <cell_type>EC</cell_type> to <cell_type>PBL</cell_type> suboptimally stimulated with <protein>mAb OKT3</protein> .


We now report that EC costimulation causes increased levels of IL-2 mRNA as a result of increased IL-2 transcription in PBL .

We now report that <cell_type>EC</cell_type> costimulation causes increased levels of <rna>IL-2 mRNA</rna> as a result of increased <protein>IL-2</protein> transcription in <cell_type>PBL</cell_type> .


We therefore examined the effects of EC on T cell nuclear factors known to regulate IL-2 transcription , including c-jun and c-fos-two components of the transcription factor AP-1 , NFAT , and others .

We therefore examined the effects of <cell_type>EC</cell_type> on <protein>T cell nuclear factors</protein> known to regulate <protein>IL-2</protein> transcription , including <protein>c-jun</protein> and <protein>c-fos-two components</protein> of the <protein>transcription factor</protein> <protein>AP-1</protein> , <protein>NFAT</protein> , and others .


PBL constitutively express c-jun transcripts , and the level of c-jun mRNA is not altered by PHA activation in the absence or presence of EC .

<cell_type>PBL</cell_type> constitutively express <protein>c-jun transcripts</protein> , and the level of <rna>c-jun mRNA</rna> is not altered by <protein>PHA</protein> activation in the absence or presence of <cell_type>EC</cell_type> .


In contrast , c-fos mRNA is absent from resting T cells and is induced on PHA activation .

In contrast , <rna>c-fos mRNA</rna> is absent from resting <cell_type>T cells</cell_type> and is induced on <protein>PHA</protein> activation .


EC alone do not induce c-fos mRNA but augment the level of c-fos mRNA in PHA-activated T cells by 3- to 10-fold .

<cell_type>EC</cell_type> alone do not induce <rna>c-fos mRNA</rna> but augment the level of <rna>c-fos mRNA</rna> in <cell_type>PHA-activated T cells</cell_type> by 3- to 10-fold .


This effect is largely independent of the CD2 : lymphocyte function-associated Ag-3 pathway .


Gel-shift analysis reveals the constitutive presence of nuclear factors in resting PBL that bind to the proximal AP-1 site of the IL-2 promoter and that contain immunoreactive c-Jun but not c-Fos protein .

Gel-shift analysis reveals the constitutive presence of nuclear factors in <cell_type>resting PBL</cell_type> that bind to the <dna>proximal AP-1 site</dna> of the <dna>IL-2 promoter</dna> and that contain immunoreactive <protein>c-Jun</protein> but not <protein>c-Fos</protein> protein .


In contrast , AP-1 from PHA-activated cells contains c-Jun and low levels of c-Fos .

In contrast , <protein>AP-1</protein> from <cell_type>PHA-activated cells</cell_type> contains <protein>c-Jun</protein> and low levels of <protein>c-Fos</protein> .


Strikingly , costimulation with EC results in a dramatic increase ( up to 15-fold ) in the c-Fos content of AP-1 .

Strikingly , costimulation with <cell_type>EC</cell_type> results in a dramatic increase ( up to 15-fold ) in the <protein>c-Fos</protein> content of <protein>AP-1</protein> .


Levels of other nuclear factors involved in IL-2 regulation were not altered by EC , although NFAT-DNA complexes migrated at a slightly different mobility .

Levels of other <protein>nuclear factors</protein> involved in <protein>IL-2</protein> regulation were not altered by <cell_type>EC</cell_type> , although <protein>NFAT-DNA complexes</protein> migrated at a slightly different mobility .


In summary , our data suggest that changes in the composition of transcription factor AP-1 is a key molecular mechanism for increasing IL-2 transcription and may underlie the phenomenon of costimulation by EC .

In summary , our data suggest that changes in the composition of <protein>transcription factor</protein> <protein>AP-1</protein> is a key molecular mechanism for increasing <protein>IL-2</protein> transcription and may underlie the phenomenon of costimulation by <cell_type>EC</cell_type> .


Transcriptional activation of human zeta 2 globin promoter by the alpha globin regulatory element ( HS-40 ) : functional role of specific nuclear factor-DNA complexes .

Transcriptional activation of <dna>human zeta 2 globin promoter</dna> by the <dna>alpha globin regulatory element</dna> ( <dna>HS-40</dna> ) : functional role of specific <protein>nuclear factor-DNA complexes</protein> .


We studied the functional interaction between human embryonic zeta 2 globin promoter and the alpha globin regulatory element ( HS-40 ) located 40 kb upstream of the zeta 2 globin gene .

We studied the functional interaction between <dna>human embryonic zeta 2 globin promoter</dna> and the <dna>alpha globin regulatory element</dna> ( <dna>HS-40</dna> ) located <dna>40 kb upstream</dna> of the <dna>zeta 2 globin gene</dna> .


It was shown by transient expression assay that HS-40 behaved as an authentic enhancer for high-level zeta 2 globin promoter activity in K562 cells , an erythroid cell line of embryonic and/or fetal origin .

It was shown by transient expression assay that <dna>HS-40</dna> behaved as an authentic <dna>enhancer</dna> for high-level <dna>zeta 2 globin promoter</dna> activity in <cell_line>K562 cells</cell_line> , an erythroid cell line of embryonic and/or fetal origin .


Although sequences located between -559 and -88 of the zeta 2 globin gene were dispensable for its expression on enhancerless plasmids , they were required for the HS-40 enhancer -mediated activity of the zeta 2 globin promoter .

Although sequences located between -559 and -88 of the <dna>zeta 2 globin gene</dna> were dispensable for its expression on <dna>enhancerless plasmids</dna> , they were required for the <dna>HS-40 enhancer</dna> -mediated activity of the <dna>zeta 2 globin promoter</dna> .


Site-directed mutagenesis demonstrated that this HS-40 enhancer- zeta 2 globin promoter interaction is mediated by the two GATA-1 factor binding motifs located at -230 and -104 , respectively .

Site-directed mutagenesis demonstrated that this <dna>HS-40</dna> enhancer- <dna>zeta 2 globin promoter</dna> interaction is mediated by the two GATA-1 factor binding motifs located at -230 and -104 , respectively .


The functional domains of HS-40 were also mapped .

The functional domains of <dna>HS-40</dna> were also mapped .


Bal 31 deletion mapping data suggested that one GATA-1 motif , one GT motif , and two NF-E2/AP1 motifs together formed the functional core of HS-40 in the erythroid-specific activation of the zeta 2 globin promoter .

Bal 31 deletion mapping data suggested that one GATA-1 motif , one GT motif , and two NF-E2/AP1 motifs together formed the functional core of <dna>HS-40</dna> in the erythroid-specific activation of the <dna>zeta 2 globin promoter</dna> .


Site-directed mutagenesis further demonstrated that the enhancer function of one of the two NF-E2/AP1 motifs of HS-40 is mediated through its binding to NF-E2 but not AP1 transcription factor .

Site-directed mutagenesis further demonstrated that the <dna>enhancer</dna> function of one of the two NF-E2/AP1 motifs of <dna>HS-40</dna> is mediated through its binding to <protein>NF-E2</protein> but not <protein>AP1 transcription factor</protein> .


Finally , we did genomic footprinting of the HS-40 enhancer region in K562 cells , adult nucleated erythroblasts , and different nonerythroid cells .

Finally , we did genomic footprinting of the <dna>HS-40 enhancer region</dna> in <cell_line>K562 cells</cell_line> , <cell_line>adult nucleated erythroblasts</cell_line> , and different <cell_type>nonerythroid cells</cell_type> .


All sequence motifs within the functional core of HS-40 , as mapped by transient expression analysis , appeared to bind a nuclear factor ( s ) in living K562 cells but not in nonerythroid cells .

All sequence motifs within the functional core of <dna>HS-40</dna> , as mapped by transient expression analysis , appeared to bind a <protein>nuclear factor</protein> ( s ) in living <cell_line>K562 cells</cell_line> but not in <cell_type>nonerythroid cells</cell_type> .


On the other hand , only one of the apparently nonfunctional sequence motifs was bound with factors in vivo .

On the other hand , only one of the apparently <dna>nonfunctional sequence motifs</dna> was bound with factors in vivo .


In comparison to K562 , nucleated erythroblasts from adult human bone marrow exhibited a similar but nonidentical pattern of nuclear factor binding in vivo at the HS-40 region .

In comparison to <cell_line>K562</cell_line> , <cell_line>nucleated erythroblasts</cell_line> from adult human bone marrow exhibited a similar but nonidentical pattern of <protein>nuclear factor</protein> binding in vivo at the <dna>HS-40</dna> region .


These data suggest that transcriptional activation of human embryonic zeta 2 globin gene and the fetal/adult alpha globin genes is mediated by erythroid cell-specific and developmental stage-specific nuclear factor-DNA complexes which form at the enhancer ( HS-40 ) and the globin promoters .

These data suggest that transcriptional activation of <dna>human embryonic zeta 2 globin gene</dna> and the <dna>fetal/adult alpha globin genes</dna> is mediated by erythroid cell-specific and <protein>developmental stage-specific nuclear factor-DNA complexes</protein> which form at the <dna>enhancer</dna> ( <dna>HS-40</dna> ) and the <dna>globin promoters</dna> .


Transcriptional regulation of the pyruvate kinase erythroid-specific promoter .

Transcriptional regulation of the <dna>pyruvate kinase erythroid-specific promoter</dna> .


Mammal pyruvate kinases are encoded by two genes .

<protein>Mammal pyruvate kinases</protein> are encoded by two genes .


The L gene produces the erythroid ( R-PK ) or the hepatic ( L-PK ) isozymes by the alternative use of two promoters .

The <dna>L gene</dna> produces the <protein>erythroid</protein> ( <protein>R-PK</protein> ) or the <protein>hepatic ( L-PK ) isozymes</protein> by the alternative use of two <dna>promoters</dna> .


We report the characterization of the cis- and trans-acting elements involved in the tissue-specific activity of the L gene erythroid promoter .

We report the characterization of the <dna>cis- and trans-acting elements</dna> involved in the tissue-specific activity of the <dna>L gene erythroid promoter</dna> .


A R-PK DNA fragment extending from -870 to +54 relative to the cap site confers erythroid specificity to a reporter gene .

A <dna>R-PK DNA fragment</dna> extending from -870 to +54 relative to the <dna>cap site</dna> confers erythroid specificity to a <dna>reporter gene</dna> .


Within this region , we define a minimal promoter ( -62 to +54 ) that displays erythroid-specific activity and contains two DNA binding sites .

Within this region , we define a <dna>minimal promoter</dna> ( -62 to +54 ) that displays erythroid-specific activity and contains two DNA binding sites .


One , located at -50 , binds members of the CCACC/Sp1 family and the other , located at -20 , binds the erythroid factor GATA-1 .

One , located at -50 , binds members of the <protein>CCACC/Sp1 family</protein> and the other , located at -20 , binds the <protein>erythroid factor GATA-1</protein> .


Although the -20 GATA binding site ( AGATAA ) is also a potential TFIID binding site , it does not bind TFIID .

Although the -20 <dna>GATA binding site</dna> ( AGATAA ) is also a potential <dna>TFIID binding site</dna> , it does not bind <protein>TFIID</protein> .


Furthermore , the substitution of this GATA binding site by a canonical TFIID binding site suppresses the promoter activity .

Furthermore , the substitution of this <dna>GATA binding site</dna> by a canonical <dna>TFIID binding site</dna> suppresses the promoter activity .


Mutations and deletions of both sites indicate that only the association of CCACC/Sp1 and GATA binding sites can drive efficient and tissue-specific expression of this R-PK minimal promoter .

Mutations and deletions of both sites indicate that only the association of <protein>CCACC/Sp1</protein> and <dna>GATA binding sites</dna> can drive efficient and tissue-specific expression of this <protein>R-PK</protein> <dna>minimal promoter</dna> .


Finally , by co-transfection experiments , we study the elements involved in the hGATA-1 transactivation of the R-PK promoter in HeLa cells .

Finally , by co-transfection experiments , we study the elements involved in the hGATA-1 transactivation of the <dna>R-PK promoter</dna> in <cell_line>HeLa cells</cell_line> .


Protease treatment of nuclear extracts distinguishes between class II MHC X1 box DNA-binding proteins in wild-type and class II-deficient B cells .

Protease treatment of nuclear extracts distinguishes between <protein>class II MHC X1 box DNA-binding proteins</protein> in <cell_line>wild-type and class II-deficient B cells</cell_line> .


The X box region is critical for directing the expression of class II major histocompatibility complex genes in B lymphocytes .

The <dna>X box region</dna> is critical for directing the expression of <dna>class II major histocompatibility complex genes</dna> in <cell_type>B lymphocytes</cell_type> .


Although several class II promoter-specific DNA binding factors have been described , only the X box region factor , RFX , shows a genetic correlation with class II expression , being deficient in some B cell lines derived from patients with class II-deficient congenital immunodeficiency .

Although several <protein>class II promoter-specific DNA binding factors</protein> have been described , only the <dna>X box region</dna> factor , <protein>RFX</protein> , shows a genetic correlation with class II expression , being deficient in some <cell_line>B cell lines</cell_line> derived from patients with class II-deficient congenital immunodeficiency .


To further evaluate the role of X box DNA-binding proteins in class II gene expression , the role of the X box region was examined in both class II-positive and -negative lymphoid cells .

To further evaluate the role of <protein>X box DNA-binding proteins</protein> in <dna>class II gene</dna> expression , the role of the <dna>X box region</dna> was examined in both <cell_line>class II-positive</cell_line> and <cell_line>-negative lymphoid cells</cell_line> .


In addition to the wild-type B cell line Raji , two class II transcriptional mutant cell lines , SJO and RJ2.2.5 , and Jurkat , a class II negative T cell line , were examined .

In addition to the <cell_line>wild-type B cell line Raji</cell_line> , <cell_line>two class II transcriptional mutant cell lines</cell_line> , <cell_line>SJO</cell_line> and <cell_line>RJ2.2.5</cell_line> , and <cell_line>Jurkat</cell_line> , a <cell_line>class II negative T cell line</cell_line> , were examined .


In contrast to wild-type B cells , neither of the class II mutant cell lines could use the X box region to direct the expression of a transiently transfected reporter gene , indicating that the X box-dependent transcriptional pathway is defective in these cells .

In contrast to <cell_line>wild-type B cells</cell_line> , neither of the <cell_line>class II mutant cell lines</cell_line> could use the <dna>X box region</dna> to direct the expression of a transiently transfected <dna>reporter gene</dna> , indicating that the X box-dependent transcriptional pathway is defective in these cells .


The binding activity of the X1 box DNA-binding protein RFX was examined and found to be present in wild-type B cells and the mutant RJ2.2.5 but was absent in SJO and Jurkat .

The binding activity of the <protein>X1 box DNA-binding protein</protein> <protein>RFX</protein> was examined and found to be present in <cell_line>wild-type B cells</cell_line> and the mutant <cell_line>RJ2.2.5</cell_line> but was absent in <cell_line>SJO</cell_line> and <cell_line>Jurkat</cell_line> .


However , other X1 box-specific activities were detected in all these cell lines .

However , other X1 box-specific activities were detected in all these <cell_line>cell lines</cell_line> .


To determine whether these different X1 box activities represented distinct DNA binding proteins or multimeric forms of the same factor ( s ) , protease treatment of the crude nuclear extracts followed by DNA-binding assays were carried out and demonstrated that B cell extracts contain at least two X1-specific factors .

To determine whether these different X1 box activities represented distinct <protein>DNA binding proteins</protein> or multimeric forms of the same factor ( s ) , <protein>protease</protein> treatment of the crude nuclear extracts followed by DNA-binding assays were carried out and demonstrated that B cell extracts contain at least two <protein>X1-specific factors</protein> .


One of these cleaved products ( band 1 pk ) correlates with RFX activity .

One of these cleaved products ( band 1 pk ) correlates with <protein>RFX</protein> activity .


A similar comparison with protease-treated extracts prepared from Jurkat cells demonstrated the presence of the band 1pk activity despite an absence of the native RFX activity .

A similar comparison with protease-treated extracts prepared from <cell_line>Jurkat cells</cell_line> demonstrated the presence of the band 1pk activity despite an absence of the native <protein>RFX</protein> activity .


In contrast , protease treatment and analysis of SJO extracts showed no detectable levels of the band 1pk activity .

In contrast , protease treatment and analysis of <cell_line>SJO</cell_line> extracts showed no detectable levels of the band 1pk activity .


These results demonstrate that multiple X1 box-specific DNA-binding activities exist in all lymphoid cells , but the presence of an actively binding RFX species correlates with class II transcription .

These results demonstrate that multiple X1 box-specific DNA-binding activities exist in all <cell_type>lymphoid cells</cell_type> , but the presence of an actively binding <protein>RFX</protein> species correlates with class II transcription .


Human immunodeficiency viruses containing heterologous enhancer/promoters are replication competent and exhibit different lymphocyte tropisms .

Human immunodeficiency viruses containing <dna>heterologous enhancer/promoters</dna> are replication competent and exhibit different lymphocyte tropisms .


The human immunodeficiency virus ( HIV ) type 1 long terminal repeat ( LTR ) contains binding sites for nuclear factor kappa B ( NF-kappa B ) and the constitutively expressed transcription factor Sp1 , both of which are highly conserved in HIV and simian immunodeficiency virus isolates .

The <dna>human immunodeficiency virus ( HIV ) type 1 long terminal repeat</dna> ( <dna>LTR</dna> ) contains binding sites for <protein>nuclear factor kappa B</protein> ( <protein>NF-kappa B</protein> ) and the constitutively expressed <protein>transcription factor Sp1</protein> , both of which are highly conserved in HIV and simian immunodeficiency virus isolates .


To delineate the effects of these motifs on the replicative capacity of HIV and to explore the possibility of extending the virus host range , known heterologous enhancer/promoters were inserted into the HIV-1 LTR in place of the NF-kappa B and Sp1 binding sites .

To delineate the effects of these motifs on the replicative capacity of HIV and to explore the possibility of extending the virus host range , known <dna>heterologous enhancer/promoters</dna> were inserted into the <dna>HIV-1 LTR</dna> in place of the <protein>NF-kappa B</protein> and <dna>Sp1 binding sites</dna> .


The effects of these substitutions on viral replication in transfected HeLa cells and on HIV infection of human peripheral blood lymphocytes or continuous T-leukemia cell lines were evaluated .

The effects of these substitutions on viral replication in transfected <cell_line>HeLa cells</cell_line> and on HIV infection of <cell_type>human peripheral blood lymphocytes</cell_type> or <cell_line>continuous T-leukemia cell lines</cell_line> were evaluated .


HIVs in which the NF-kappa B/Sp1 enhancer plus the downstream TATA element were replaced with heterologous enhancer/promoters were also constructed .

HIVs in which the <dna>NF-kappa B/Sp1 enhancer</dna> plus the <dna>downstream TATA element</dna> were replaced with <dna>heterologous enhancer/promoters</dna> were also constructed .


Viruses containing the human cytomegalovirus immediate-early enhancer exhibited infectious kinetics similar to that of wild-type HIV in activated human peripheral blood lymphocytes and AA2 cells but replicated less efficiently in H9 and CEM cells .

Viruses containing the <dna>human cytomegalovirus immediate-early enhancer</dna> exhibited infectious kinetics similar to that of wild-type HIV in <cell_type>activated human peripheral blood lymphocytes</cell_type> and <cell_line>AA2 cells</cell_line> but replicated less efficiently in <cell_line>H9 and CEM cells</cell_line> .


These studies indicate that heterologous enhancer elements are capable of restoring Tat responsiveness to the HIV LTR in the context of directing reporter gene expression as well as in the production of infectious progeny virions .

These studies indicate that <dna>heterologous enhancer elements</dna> are capable of restoring <protein>Tat</protein> responsiveness to the <dna>HIV LTR</dna> in the context of directing <dna>reporter gene</dna> expression as well as in the production of infectious progeny virions .


Tyrosine phosphorylation is a mandatory proximal step in radiation-induced activation of the protein kinase C signaling pathway in human B-lymphocyte precursors [ published erratum appears in Proc Natl Acad Sci U S A 1993 Apr 15 ; 90 ( 8 ) : 3775 ]

Tyrosine phosphorylation is a mandatory proximal step in radiation-induced activation of the <protein>protein kinase C</protein> signaling pathway in <cell_type>human B-lymphocyte precursors</cell_type> [ published erratum appears in Proc Natl Acad Sci U S A 1993 Apr 15 ; 90 ( 8 ) : 3775 ]


Ionizing radiation triggers a signal in human B-lymphocyte precursors that is intimately linked to an active protein-tyrosine kinase regulatory pathway .

Ionizing radiation triggers a signal in <cell_type>human B-lymphocyte precursors</cell_type> that is intimately linked to an active <protein>protein-tyrosine kinase</protein> regulatory pathway .


We show that in B-lymphocyte precursors , irradiation with gamma-rays leads to ( i ) stimulation of phosphatidylinositol turnover ; ( ii ) downstream activation by covalent modification of multiple serine-specific protein kinases , including protein kinase C ; and ( iii ) activation of nuclear factor kappa B .

We show that in <cell_type>B-lymphocyte precursors</cell_type> , irradiation with gamma-rays leads to ( i ) stimulation of phosphatidylinositol turnover ; ( ii ) downstream activation by covalent modification of multiple <protein>serine-specific protein kinases</protein> , including <protein>protein kinase C</protein> ; and ( iii ) activation of <protein>nuclear factor kappa B</protein> .


All of the radiation-induced signals were effectively prevented by the protein-tyrosine kinase inhibitors genistein and herbimycin A .

All of the radiation-induced signals were effectively prevented by the <protein>protein-tyrosine kinase inhibitors genistein and herbimycin A</protein> .


Thus , tyrosine phosphorylation is an important and perhaps mandatory proximal step in the activation of the protein kinase C signaling cascade in human B-lymphocyte precursors .

Thus , tyrosine phosphorylation is an important and perhaps mandatory proximal step in the activation of the <protein>protein kinase C</protein> signaling cascade in <cell_type>human B-lymphocyte precursors</cell_type> .


Our report expands current knowledge of the radiation-induced signaling cascade by clarifying the chronological sequence of biochemical events that follow irradiation .


Detection of adenovirus DNA in peripheral blood mononuclear cells by polymerase chain reaction assay .

Detection of <dna>adenovirus DNA</dna> in <cell_type>peripheral blood mononuclear cells</cell_type> by polymerase chain reaction assay .


Adenovirus can establish persistent infections which may reactivate and cause disease in immunocompromised hosts .