Transcription specific differences visualized by fluorescence in situ hybridization pattern on interphase nuclei of different cell types .


Application of a `` formamide free '' and thus `` material preserving '' in situ hybridization technique using the cDNA of the myf3 gene revealed the following results : Human rhabdomyosarcoma cells , characterized by a high expression of myf3 show intensive hybridization signals in their interphase .

Application of a `` formamide free '' and thus `` material preserving '' in situ hybridization technique using the <dna>cDNA</dna> of the <dna>myf3 gene</dna> revealed the following results : <cell_type>Human rhabdomyosarcoma cells</cell_type> , characterized by a high expression of <dna>myf3</dna> show intensive hybridization signals in their interphase .


RNase treatment prior to hybridization considerably reduces the size of this signals .

<protein>RNase</protein> treatment prior to hybridization considerably reduces the size of this signals .


In comparison , isolated nuclei of human lymphocytes in which no need for the expression of this gene exists , show barely hybridization signals .

In comparison , isolated nuclei of <cell_type>human lymphocytes</cell_type> in which no need for the expression of this gene exists , show barely hybridization signals .


Correspondingly , RNase treatment had no effect on hybridization pattern at all .

Correspondingly , <protein>RNase</protein> treatment had no effect on hybridization pattern at all .


In conclusion an increased transcription efficiency of a cell type specific gene is accompanied by a higher hybridization accessibility in the corresponding cell nuclei .


Oncogenicity of human papillomavirus- or adenovirus-transformed cells correlates with resistance to lysis by natural killer cells .

Oncogenicity of <cell_line>human papillomavirus- or adenovirus-transformed cells</cell_line> correlates with resistance to lysis by <cell_type>natural killer cells</cell_type> .


The reasons for the dissimilar oncogenicities of human adenoviruses and human papillomaviruses ( HPV ) in humans are unknown but may relate to differences in the capacities of the E1A and E7 proteins to target cells for rejection by the host natural killer ( NK ) cell response .

The reasons for the dissimilar oncogenicities of human adenoviruses and human papillomaviruses ( HPV ) in humans are unknown but may relate to differences in the capacities of the <protein>E1A</protein> and <protein>E7 proteins</protein> to <cell_type>target cells</cell_type> for rejection by the <cell_type>host natural killer ( NK ) cell</cell_type> response .


As one test of this hypothesis , we compared the abilities of E1A -and E7 -expressing human fibroblastic or keratinocyte-derived human cells to be selectively killed by either unstimulated or interferon ( IFN ) -activated NK cells .

As one test of this hypothesis , we compared the abilities of <protein>E1A</protein> -and <protein>E7</protein> -expressing <cell_line>human fibroblastic or keratinocyte-derived human cells</cell_line> to be selectively killed by either <cell_type>unstimulated</cell_type> or <cell_line>interferon ( IFN ) -activated NK cells</cell_line> .


Cells expressing the E1A oncoprotein were selectively killed by unstimulated NK cells , while the same parental cells but expressing the HPV type 16 ( HPV-16 ) or HPV-18 E7 oncoprotein were resistant to NK cell lysis .

Cells expressing the <protein>E1A oncoprotein</protein> were selectively killed by <cell_line>unstimulated NK cells</cell_line> , while the same <cell_type>parental cells</cell_type> but expressing the HPV type 16 ( HPV-16 ) or HPV-18 <protein>E7 oncoprotein</protein> were resistant to NK cell lysis .


The ability of IFN-activated NK cells to selectively kill virally transformed cells depends on IFN 's ability to induce resistance to NK cell lysis in normal ( i.e. , non-viral oncogene-expressing ) but not virally transformed cells .

The ability of <cell_line>IFN-activated NK cells</cell_line> to selectively kill virally transformed cells depends on <protein>IFN</protein> 's ability to induce resistance to NK cell lysis in normal ( i.e. , <cell_line>non-viral oncogene-expressing</cell_line> ) but not <cell_line>virally transformed cells</cell_line> .


E1A blocked IFN 's induction of cytolytic resistance , resulting in the selective lysis of adenovirus-transformed cells by IFN-activated NK cells .

<protein>E1A</protein> blocked <protein>IFN</protein> 's induction of cytolytic resistance , resulting in the selective lysis of <cell_line>adenovirus-transformed cells</cell_line> by <cell_line>IFN-activated NK cells</cell_line> .


The extent of IFN -induced NK cell killing of E1A-expressing cells was proportional to the level of E1A expression and correlated with the ability of E1A to block IFN -stimulated gene expression in target cells .

The extent of <protein>IFN</protein> -induced NK cell killing of <cell_line>E1A-expressing cells</cell_line> was proportional to the level of <protein>E1A</protein> expression and correlated with the ability of <protein>E1A</protein> to block <protein>IFN</protein> -stimulated gene expression in <cell_type>target cells</cell_type> .


In contrast , E7 blocked neither IFN -stimulated gene expression nor IFN 's induction of cytolytic resistance , thereby precluding the selective lysis of HPV-transformed cells by IFN-activated NK cells .

In contrast , <protein>E7</protein> blocked neither <protein>IFN</protein> -stimulated gene expression nor <protein>IFN</protein> 's induction of cytolytic resistance , thereby precluding the selective lysis of <cell_line>HPV-transformed cells</cell_line> by <cell_line>IFN-activated NK cells</cell_line> .


In conclusion , E1A expression marks cells for destruction by the host NK cell response , whereas the E7 oncoprotein lacks this activity .

In conclusion , <protein>E1A</protein> expression marks cells for destruction by the host <cell_type>NK cell</cell_type> response , whereas the <protein>E7 oncoprotein</protein> lacks this activity .


Regulation of IkB alpha phosphorylation by PKC- and Ca ( 2+ ) -dependent signal transduction pathways .

Regulation of <protein>IkB alpha</protein> phosphorylation by PKC- and Ca ( 2+ ) -dependent signal transduction pathways .


The Ca ( 2+ ) -dependent phosphatase calcineurin , a target of FK506 and CsA , synergizes with PKC -induced activation of nuclear factor ( NF ) -kappa B in T cell lines .

The <protein>Ca ( 2+ ) -dependent phosphatase</protein> <protein>calcineurin</protein> , a target of FK506 and CsA , synergizes with <protein>PKC</protein> -induced activation of <protein>nuclear factor ( NF ) -kappa B</protein> in <cell_line>T cell lines</cell_line> .


We have investigated whether this synergy is present in other cell types and the mechanism ( s ) by which these two pathways lead to NF-kappa B activation .

We have investigated whether this synergy is present in other cell types and the mechanism ( s ) by which these two pathways lead to <protein>NF-kappa B</protein> activation .


While this synergy is present in other cell types , in the monocytic cell line U937 calcineurin is also sufficient to activate NF-kappa B .

While this synergy is present in other cell types , in the <cell_line>monocytic cell line U937</cell_line> <protein>calcineurin</protein> is also sufficient to activate <protein>NF-kappa B</protein> .


Having previously shown that Ca ( 2+ ) - and PKC-dependent pathways synergize by accelerating the degradation of IkB alpha , we focused on the regulation of IkB alpha phosphorylation .

Having previously shown that Ca ( 2+ ) - and PKC-dependent pathways synergize by accelerating the degradation of <protein>IkB alpha</protein> , we focused on the regulation of <protein>IkB alpha</protein> phosphorylation .


While PKC -dependent pathways sequentially result in the phosphorylation and in an incomplete degradation of IkB alpha in T cell lines , co-activation of Ca ( 2+ ) -dependent pathways accelerates the rate of IkB alpha phosphorylation and results in its complete degradation .

While <protein>PKC</protein> -dependent pathways sequentially result in the phosphorylation and in an incomplete degradation of <protein>IkB alpha</protein> in <cell_line>T cell lines</cell_line> , co-activation of Ca ( 2+ ) -dependent pathways accelerates the rate of <protein>IkB alpha</protein> phosphorylation and results in its complete degradation .


Activation of Ca ( 2+ ) -dependent pathways alone do not result in the phosphorylation and/or degradation of IkB alpha in Jurkat T or in U937 cells .

Activation of Ca ( 2+ ) -dependent pathways alone do not result in the phosphorylation and/or degradation of <protein>IkB alpha</protein> in <cell_line>Jurkat T</cell_line> or in <cell_line>U937 cells</cell_line> .


Treatment of T cells with the selective PKC inhibitor GF109203X abrogates the PMA-induced IkB alpha phosphorylation/degradation irrespective of activation of Ca ( 2+ ) -dependent pathways , but not the phosphorylation and degradation of IkB alpha induced by TNF-alpha , a PKC -independent stimulus .

Treatment of <cell_type>T cells</cell_type> with the selective <protein>PKC</protein> inhibitor GF109203X abrogates the PMA-induced <protein>IkB alpha</protein> phosphorylation/degradation irrespective of activation of Ca ( 2+ ) -dependent pathways , but not the phosphorylation and degradation of <protein>IkB alpha</protein> induced by <protein>TNF-alpha</protein> , a <protein>PKC</protein> -independent stimulus .


Contrary to the interaction with PKC , Ca ( 2+ ) -dependent pathways synergize with TNF-alpha not at the level of IkB alpha phosphorylation , but at the level of its degradation .

Contrary to the interaction with <protein>PKC</protein> , Ca ( 2+ ) -dependent pathways synergize with <protein>TNF-alpha</protein> not at the level of <protein>IkB alpha</protein> phosphorylation , but at the level of its degradation .


These results indicate that Ca ( 2+ ) -dependent pathways , including the phosphatase calcineurin , participate in the regulation of NF-kappa B in a cell specific fashion and synergize with PKC -dependent and -independent pathways at the level of IkB alpha phosphorylation and degradation .

These results indicate that Ca ( 2+ ) -dependent pathways , including the <protein>phosphatase</protein> <protein>calcineurin</protein> , participate in the regulation of <protein>NF-kappa B</protein> in a cell specific fashion and synergize with <protein>PKC</protein> -dependent and -independent pathways at the level of <protein>IkB alpha</protein> phosphorylation and degradation .


Vitamin E therapy of acute CCl4-induced hepatic injury in mice is associated with inhibition of nuclear factor kappa B binding .

Vitamin E therapy of acute CCl4-induced hepatic injury in mice is associated with inhibition of <protein>nuclear factor kappa B</protein> binding .


Oxidative stress , with reactive oxygen intermediate formation , may represent a common mechanism by which liver injury is induced by diverse etiologies .


Oxidative stress enhances nuclear factor kappa B ( NF-kappa B ) activity , and NF-kappa B activity has been shown to enhance the expression of cytotoxic cytokines .

Oxidative stress enhances <protein>nuclear factor kappa B</protein> ( <protein>NF-kappa B</protein> ) activity , and <protein>NF-kappa B</protein> activity has been shown to enhance the expression of <protein>cytotoxic cytokines</protein> .


Acute hepatic injury caused by reactive oxygen intermediate production was induced by an intraperitoneal injection of CCl4 in mice .


This injury was significantly inhibited by intravenous pretreatment of the mice with a water-soluble emulsion of alpha-tocopherol .


Alpha-tocopherol treatment of the mice given the CCl4 also reduced the NF-kappa B binding to levels approaching those found in normal mice .

Alpha-tocopherol treatment of the mice given the CCl4 also reduced the <protein>NF-kappa B</protein> binding to levels approaching those found in normal mice .


In vitro treatment of a monocyte/macrophage cell line with CCl4 led to enhanced NF-kappa B binding and an increase in tumor necrosis factor-alpha ( TNF-alpha ) messenger RNA levels .

In vitro treatment of a monocyte/macrophage cell line with CCl4 led to enhanced <protein>NF-kappa B</protein> binding and an increase in <rna>tumor necrosis factor-alpha ( TNF-alpha ) messenger RNA</rna> levels .


Liver specimens taken from patients with acute fulminant hepatitis had markedly increased NF-kappa B binding activity in comparison with the binding of normal livers .

Liver specimens taken from patients with acute fulminant hepatitis had markedly increased <protein>NF-kappa B</protein> binding activity in comparison with the binding of normal livers .


These data demonstrate that abolishing acute hepatic injury with alpha-tocopherol , a free radical scavenger , also eliminated increased NF-kappa B binding .

These data demonstrate that abolishing acute hepatic injury with alpha-tocopherol , a free radical scavenger , also eliminated increased <protein>NF-kappa B</protein> binding .


It is tempting to speculate that enhanced NF-kappa B expression caused by free radical production/oxidative stress may modulate liver injury , perhaps through an effect on cytotoxic cytokine synthesis .

It is tempting to speculate that enhanced <protein>NF-kappa B</protein> expression caused by free radical production/oxidative stress may modulate liver injury , perhaps through an effect on <protein>cytotoxic cytokine</protein> synthesis .


Immunosuppression by glucocorticoids : inhibition of NF-kappa B activity through induction of I kappa B synthesis [ see comments ]

Immunosuppression by glucocorticoids : inhibition of <protein>NF-kappa B</protein> activity through induction of <protein>I kappa B</protein> synthesis [ see comments ]


Glucocorticoids are among the most potent anti-inflammatory and immunosuppressive agents .


They inhibit synthesis of almost all known cytokines and of several cell surface molecules required for immune function , but the mechanism underlying this activity has been unclear. Here it is shown that glucocorticoids are potent inhibitors of nuclear factor kappa B ( NF-kappa B ) activation in mice and cultured cells .

They inhibit synthesis of almost all known <protein>cytokines</protein> and of several <protein>cell surface molecules</protein> required for immune function , but the mechanism underlying this activity has been unclear. Here it is shown that glucocorticoids are potent inhibitors of <protein>nuclear factor kappa B</protein> ( <protein>NF-kappa B</protein> ) activation in mice and <cell_line>cultured cells</cell_line> .


This inhibition is mediated by induction of the I kappa B alpha inhibitory protein , which traps activated NF-kappa B in inactive cytoplasmic complexes .

This inhibition is mediated by induction of the <protein>I kappa B</protein> alpha inhibitory protein , which traps activated <protein>NF-kappa B</protein> in <protein>inactive cytoplasmic complexes</protein> .


Because NF-kappa B activates many immunoregulatory genes in response to pro-inflammatory stimuli , the inhibition of its activity can be a major component of the anti-inflammatory activity of glucocorticoids .

Because <protein>NF-kappa B</protein> activates many <dna>immunoregulatory genes</dna> in response to pro-inflammatory stimuli , the inhibition of its activity can be a major component of the anti-inflammatory activity of glucocorticoids .


Transcriptional repression of the interleukin-2 gene by vitamin D3 : direct inhibition of NFATp/AP-1 complex formation by a nuclear hormone receptor .

Transcriptional repression of the <dna>interleukin-2 gene</dna> by vitamin D3 : direct inhibition of <protein>NFATp/AP-1 complex</protein> formation by a <protein>nuclear hormone receptor</protein> .


T-lymphocyte proliferation is suppressed by 1 , 25-dihydroxyvitamin D3 [ 1 , 25 ( OH ) 2D3 ] , the active metabolite of vitamin D3 , and is associated with a decrease in interleukin 2 ( IL-2 ) , gamma interferon , and granulocyte-macrophage colony-stimulating factor mRNA levels .


We report here that 1 , 25 ( OH ) 2D3-mediated repression in Jurkat cells is cycloheximide resistant , suggesting that it is a direct transcriptional repressive effect on IL-2 expression by the vitamin D3 receptor ( VDR ) .

We report here that 1 , 25 ( OH ) 2D3-mediated repression in <cell_line>Jurkat cells</cell_line> is cycloheximide resistant , suggesting that it is a direct transcriptional repressive effect on <protein>IL-2</protein> expression by the <protein>vitamin D3 receptor</protein> ( <protein>VDR</protein> ) .


We therefore examined vitamin D3-mediated repression of activated IL-2 expression by cotransfecting Jurkat cells with IL-2 promoter/reporter constructs and a VDR overexpression vector and by DNA binding .

We therefore examined vitamin D3-mediated repression of activated <protein>IL-2</protein> expression by cotransfecting <cell_line>Jurkat cells</cell_line> with <dna>IL-2 promoter/reporter constructs</dna> and a <dna>VDR overexpression vector</dna> and by DNA binding .


We delineated an element conferring both DNA binding by the receptor in vitro and 1 , 25 ( OH ) 2D3-mediated repression in vivo to a short 40-bp region encompassing an important positive regulatory element , NF-AT-1 , which is bound by a T-cell-specific transcription factor , NFATp , as well as by AP-1 .

We delineated an element conferring both DNA binding by the receptor in vitro and 1 , 25 ( OH ) 2D3-mediated repression in vivo to a short <dna>40-bp region</dna> encompassing an important <dna>positive regulatory element</dna> , <dna>NF-AT-1</dna> , which is bound by a <protein>T-cell-specific transcription factor</protein> , <protein>NFATp</protein> , as well as by <protein>AP-1</protein> .


VDR DNA-binding mutants were unable to either bind to this element in vitro or repress in vivo ; the VDR DNA-binding domain alone , however , bound the element but also could not repress IL-2 expression .

<protein>VDR DNA-binding mutants</protein> were unable to either bind to this element in vitro or repress in vivo ; the <protein>VDR DNA-binding domain</protein> alone , however , bound the element but also could not repress <protein>IL-2</protein> expression .


These results indicate that DNA binding by VDR is necessary but not sufficient to mediate IL-2 repression .

These results indicate that DNA binding by <protein>VDR</protein> is necessary but not sufficient to mediate <protein>IL-2</protein> repression .


By combining partially purified proteins in vitro , we observed the loss of the bound NFATp/AP-1-DNA complex upon inclusion of VDR or VDR-retinoid X receptor .

By combining <protein>partially purified proteins</protein> in vitro , we observed the loss of the bound <protein>NFATp/AP-1-DNA complex</protein> upon inclusion of <protein>VDR</protein> or <protein>VDR-retinoid X receptor</protein> .


Order of addition and off-rate experiments indicate that the VDR-retinoid X receptor heterodimer blocks NFATp/AP-1 complex formation and then stably associates with the NF-AT-1 element .

Order of addition and off-rate experiments indicate that the <protein>VDR-retinoid X receptor heterodimer</protein> blocks <protein>NFATp/AP-1 complex</protein> formation and then stably associates with the <dna>NF-AT-1 element</dna> .


This direct inhibition by a nuclear hormone receptor of transcriptional activators of the IL-2 gene may provide a mechanistic explanation of how vitamin derivatives can act as potent immunosuppressive agents .

This direct inhibition by a nuclear hormone receptor of <protein>transcriptional activators</protein> of the <dna>IL-2 gene</dna> may provide a mechanistic explanation of how vitamin derivatives can act as potent immunosuppressive agents .


Tissue-specific regulation of the rabbit 15-lipoxygenase gene in erythroid cells by a transcriptional silencer .

Tissue-specific regulation of the <dna>rabbit 15-lipoxygenase gene</dna> in <cell_type>erythroid cells</cell_type> by a <dna>transcriptional silencer</dna> .


The 15-lipoxygenase ( lox ) gene is expressed in a tissue-specific manner , predominantly in erythroid cells but also in airway epithelial cells and eosinophils .

The <dna>15-lipoxygenase ( lox ) gene</dna> is expressed in a tissue-specific manner , predominantly in <cell_type>erythroid cells</cell_type> but also in <cell_type>airway epithelial cells</cell_type> and <cell_type>eosinophils</cell_type> .


We demonstrate in this report that the 5 ' flanking DNA of the 15-lox gene contains sequences which down-regulate its activity in a variety of non-erythroid cell lines but not in two erythroid cell lines .

We demonstrate in this report that the <dna>5 ' flanking DNA</dna> of the <dna>15-lox gene</dna> contains sequences which down-regulate its activity in a variety of <cell_line>non-erythroid cell lines</cell_line> but not in two <cell_line>erythroid cell lines</cell_line> .


The element has characteristics of a transcriptional 'silencer ' since it functions in both orientations .

The element has characteristics of a <dna>transcriptional 'silencer '</dna> since it functions in both orientations .


The main activity of the silencer has been mapped to the first 900 bp of 5 ' flanking DNA , which contains nine binding sites for a nuclear factor present in non- erythroid cells but not in erythroid cells .

The main activity of the <dna>silencer</dna> has been mapped to the first 900 bp of <dna>5 ' flanking DNA</dna> , which contains nine binding sites for a <protein>nuclear factor</protein> present in non- <cell_type>erythroid cells</cell_type> but not in <cell_type>erythroid cells</cell_type> .


These binding sites have similar sequences and multiple copies of the binding sites confer tissue-specific down-regulation when attached to a minimal lox promoter fragment .

These binding sites have similar sequences and multiple copies of the <dna>binding sites</dna> confer tissue-specific down-regulation when attached to a <dna>minimal lox promoter fragment</dna> .


The 5 ' flanking DNA also contains a cluster of three binding sites for the GATA family of transcription factors .

The <dna>5 ' flanking DNA</dna> also contains a cluster of three <dna>binding sites</dna> for the <protein>GATA family</protein> of <protein>transcription factors</protein> .


Phosphorylation of the transcription factor NFATp inhibits its DNA binding activity in cyclosporin A-treated human B and T cells .

Phosphorylation of the <protein>transcription factor</protein> <protein>NFATp</protein> inhibits its DNA binding activity in <cell_line>cyclosporin A-treated human B</cell_line> and <cell_type>T cells</cell_type> .


Cyclosporin A ( CsA ) exerts its immunosuppressive effect by inhibiting the activity of nuclear factor of activated T cells ( NFAT ) , thus preventing transcriptional induction of several cytokine genes .

Cyclosporin A ( CsA ) exerts its immunosuppressive effect by inhibiting the activity of <protein>nuclear factor</protein> of activated <cell_type>T cells</cell_type> ( <protein>NFAT</protein> ) , thus preventing transcriptional induction of several cytokine genes .


This effect is thought to be largely mediated through inactivation of the phosphatase calcineurin , which in turn inhibits translocation of an NFAT component to the nucleus .

This effect is thought to be largely mediated through inactivation of the phosphatase <protein>calcineurin</protein> , which in turn inhibits translocation of an <protein>NFAT</protein> component to the nucleus .


Here we report that CsA treatment of Raji B and Jurkat T cell lines yields a phosphorylated form of NFATp that is inhibited in DNA-binding and in its ability to form an NFAT complex with Fos and Jun .

Here we report that CsA treatment of <cell_line>Raji B</cell_line> and <cell_line>Jurkat T cell lines</cell_line> yields a phosphorylated form of <protein>NFATp</protein> that is inhibited in DNA-binding and in its ability to form an <protein>NFAT complex</protein> with <protein>Fos</protein> and <protein>Jun</protein> .


Immunoblot analyses and metabolic labeling with [ 32P ] orthophosphate show that CsA alters NFATp migration on SDS-polyacrylamide gel electrophoresis by increasing its phosphorylation level without affecting subcellular distribution .

Immunoblot analyses and metabolic labeling with [ 32P ] orthophosphate show that CsA alters <protein>NFATp</protein> migration on SDS-polyacrylamide gel electrophoresis by increasing its phosphorylation level without affecting subcellular distribution .


Dephosphorylation by in vitro treatment with calcineurin or alkaline phosphatase restores NFATp DNA binding activity and its ability to reconstitute an NFAT complex with Fos and Jun proteins .

Dephosphorylation by in vitro treatment with <protein>calcineurin</protein> or <protein>alkaline phosphatase</protein> restores <protein>NFATp</protein> DNA binding activity and its ability to reconstitute an <protein>NFAT complex</protein> with <protein>Fos</protein> and <protein>Jun</protein> proteins .


These data point to a new mechanism for CsA-sensitive regulation of NFATp in which dephosphorylation is critical for DNA binding .

These data point to a new mechanism for CsA-sensitive regulation of <protein>NFATp</protein> in which dephosphorylation is critical for DNA binding .


Transcription factors as targets for oxidative signalling during lymphocyte activation .

<protein>Transcription factors</protein> as targets for oxidative signalling during lymphocyte activation .


We previously have demonstrated a requirement for oxidative events during cell cycle entry in T lymphocytes and have hypothesised that reactive oxygen species may act as intracellular signalling agents during lymphocyte activation .

We previously have demonstrated a requirement for oxidative events during cell cycle entry in <cell_type>T lymphocytes</cell_type> and have hypothesised that reactive oxygen species may act as intracellular signalling agents during lymphocyte activation .


In the current study , cysteamine , an aminothiol compound with antioxidant activity , has been used to further investigate the role of oxidative signalling during lymphocyte activation .


Treatment of normal human peripheral blood lymphocytes with cysteamine in vitro was found to inhibit proliferation in a dose-dependent manner , with essentially complete inhibition occurring at a dose of 400 microM .

Treatment of normal <cell_type>human peripheral blood lymphocytes</cell_type> with cysteamine in vitro was found to inhibit proliferation in a dose-dependent manner , with essentially complete inhibition occurring at a dose of 400 microM .


This inhibitory effect was limited to the first 2 h after mitogenic activation , localizing the time-frame of action of cysteamine to within the commitment period .


It therefore was of interest to establish which , if any , commitment events were affected by oxidative signalling during cell cycle entry .


Taking the IL-2 gene as a candidate , we examined the effect of cysteamine treatment on early gene expression during lymphocyte activation , and on the activity of transcription factors AP-1 , NF-kappa B , NF-AT and Oct1 , whose functions are required for expression of the IL-2 mRNA .

Taking the <dna>IL-2 gene</dna> as a candidate , we examined the effect of cysteamine treatment on <dna>early gene</dna> expression during lymphocyte activation , and on the activity of <protein>transcription factors</protein> <protein>AP-1</protein> , <protein>NF-kappa B</protein> , <protein>NF-AT</protein> and <protein>Oct1</protein> , whose functions are required for expression of the <protein>IL-2</protein> mRNA .


Cysteamine treatment inhibited both expression of the IL-2 mRNA and secretion of IL-2 into the culture medium .

Cysteamine treatment inhibited both expression of the <rna>IL-2 mRNA</rna> and secretion of <protein>IL-2</protein> into the culture medium .


The inhibitory effect of cysteamine may be mediated at least in part by an effect on transcription factor function , as the DNA binding activities of AP-1 and NF-kappa B extracted from mitogen-stimulated cells were significantly inhibited by cysteamine treatment .

The inhibitory effect of cysteamine may be mediated at least in part by an effect on <protein>transcription factor</protein> function , as the DNA binding activities of <protein>AP-1</protein> and <protein>NF-kappa B</protein> extracted from <cell_type>mitogen-stimulated cells</cell_type> were significantly inhibited by cysteamine treatment .


Interestingly , Oct1 and NF-AT DNA binding activity were not affected by cysteamine treatment , suggesting that oxidative signalling processes operate in a selective manner .


The identification of regulatory proteins , such as transcription factors , as molecular targets for oxidative signalling provides further evidence to implicate oxidative signalling as being intimately involved in the G0 to G1 phase transition in T lymphocytes .

The identification of <protein>regulatory proteins</protein> , such as <protein>transcription factors</protein> , as molecular targets for oxidative signalling provides further evidence to implicate oxidative signalling as being intimately involved in the G0 to G1 phase transition in <cell_type>T lymphocytes</cell_type> .


Sex and age distribution of 1 , 25 ( OH ) 2D3 receptors in peripheral blood mononuclear cells from normal human subjects .

Sex and age distribution of <protein>1 , 25 ( OH ) 2D3 receptors</protein> in <cell_type>peripheral blood mononuclear cells</cell_type> from normal human subjects .


Specific receptors for 1 , 25 Dihydroxyvitamin D3 have been described in human peripheral blood mononuclear cells ( PBMC ) .

Specific receptors for 1 , 25 Dihydroxyvitamin D3 have been described in human <cell_type>peripheral blood mononuclear cells</cell_type> ( <cell_type>PBMC</cell_type> ) .


We have tried to find out whether these receptors could show any difference in sex or age distribution .


Twenty two healthy men aged 21-66 yr ( mean +/- SD 41.0 +/- 13.6 ) and nineteen healthy women aged 22-60 yr ( 38.9 +/- 13.9 ) have been studied .


The mean dissociation constant ( Kd ) was similar in both sexes ( 1.35 +/- 0.70 x 10 ( -10 ) M in males , 1.13 +/- 0.66 x 10 ( -10 ) M in females ) , but the concentration of binding sites ( Nmax ) was significantly lower in females ( 2.32 +/- 0.92 fmol/10 ( 7 ) PBMC vs 4.43 +/- 1.38 fmol/10 ( 7 ) PBMC in males ; p = 0.0001 ) .

The mean dissociation constant ( Kd ) was similar in both sexes ( 1.35 +/- 0.70 x 10 ( -10 ) M in males , 1.13 +/- 0.66 x 10 ( -10 ) M in females ) , but the concentration of binding sites ( Nmax ) was significantly lower in females ( 2.32 +/- 0.92 fmol/10 ( 7 ) <cell_type>PBMC</cell_type> vs 4.43 +/- 1.38 fmol/10 ( 7 ) <cell_type>PBMC</cell_type> in males ; p = 0.0001 ) .


Neither Kd nor Nmax were significantly correlated with age .


No difference was found between pre and postmenopausal women .


Further studies are needed to elucidate if this sex difference in PBMC receptors for 1.25 Dihydroxyvitamin D3 is of any pathophysiological relevance .

Further studies are needed to elucidate if this sex difference in <protein>PBMC receptors</protein> for 1.25 Dihydroxyvitamin D3 is of any pathophysiological relevance .


Expression of Id2 and Id3 mRNA in human lymphocytes .

Expression of Id2 and Id3 mRNA in <cell_type>human lymphocytes</cell_type> .


Helix-loop-helix ( HLH ) transcription factors are involved in cellular growth and differentiation .

<protein>Helix-loop-helix ( HLH ) transcription factors</protein> are involved in cellular growth and differentiation .


The Id ( inhibitor of DNA binding and differentiation ) HLH proteins , in a dominantly negative fashion , regulate transcriptional activities of basic HLH proteins .

The <protein>Id</protein> ( inhibitor of DNA binding and differentiation ) <protein>HLH proteins</protein> , in a dominantly negative fashion , regulate transcriptional activities of <protein>basic HLH proteins</protein> .


We examined by northern hybridization the expression of Id2 and Id3 mRNA in human leukemia/lymphoma lines and patient samples , as well as resting and activated normal human lymphocytes from peripheral blood ( PBL ) .

We examined by northern hybridization the expression of <rna>Id2 and Id3 mRNA</rna> in <cell_line>human leukemia/lymphoma lines</cell_line> and patient samples , as well as resting and <cell_line>activated normal human lymphocytes</cell_line> from peripheral blood ( <cell_type>PBL</cell_type> ) .


The Id2 mRNA was abundantly expressed in 5/12 T-cell and 3/4 B-cell lines , and Id3 mRNA was detected in 4/12 T-cell and 3/4 B-cell lines .

The <rna>Id2 mRNA</rna> was abundantly expressed in <cell_line>5/12 T-cell</cell_line> and <cell_line>3/4 B-cell lines</cell_line> , and <rna>Id3 mRNA</rna> was detected in <cell_line>4/12 T-cell</cell_line> and <cell_line>3/4 B-cell lines</cell_line> .


Interestingly , Id2 , but not Id3 , mRNA was strongly expressed in 4/5 T-cell lines infected with human T-cell leukemia virus type I ( HTLV-I ) ( ATL-1k , MT-2 , S-LB1 ) and type II ( Mo ) .

Interestingly , <rna>Id2</rna> , but not <rna>Id3</rna> , mRNA was strongly expressed in <cell_line>4/5 T-cell lines</cell_line> infected with human T-cell leukemia virus type I ( HTLV-I ) ( <cell_line>ATL-1k</cell_line> , <cell_line>MT-2</cell_line> , <cell_line>S-LB1</cell_line> ) and type II ( <cell_line>Mo</cell_line> ) .


Another unexpected finding was that T-cell leukemias and T-cell lines often expressed either Id2 or Id3 mRNA .

Another unexpected finding was that T-cell leukemias and <cell_line>T-cell lines</cell_line> often expressed either <rna>Id2</rna> or <rna>Id3 mRNA</rna> .


In addition , resting PBL constitutively expressed prominent levels of Id2 mRNA , but not Id3 mRNA .

In addition , <cell_type>resting PBL</cell_type> constitutively expressed prominent levels of <rna>Id2 mRNA</rna> , but not <rna>Id3 mRNA</rna> .


Upon PHA -stimulation , Id2 expression decreased and Id3 levels increased with biphasic kinetics .

Upon <protein>PHA</protein> -stimulation , <protein>Id2</protein> expression decreased and <protein>Id3</protein> levels increased with biphasic kinetics .


Taken together , our studies revealed three unexpected findings which require further analysis : ( 1 ) expression of Id2 mRNA is often associated with lymphocytic transformation by HTLV-I or -II ; ( 2 ) T-cells usually express either Id2 or Id3 mRNA , but B-cells often express both simultaneously ; ( 3 ) non-dividing , normal PBL express high levels of Id2 and no Id3 mRNA ; and with the onset of cellular proliferation , levels of Id2 mRNA decrease while levels of Id3 mRNA increase , suggesting that regulation of expression of these closely related genes is disparate .

Taken together , our studies revealed three unexpected findings which require further analysis : ( 1 ) expression of <rna>Id2 mRNA</rna> is often associated with lymphocytic transformation by HTLV-I or -II ; ( 2 ) T-cells usually express either <protein>Id2</protein> or <rna>Id3 mRNA</rna> , but B-cells often express both simultaneously ; ( 3 ) non-dividing , normal <cell_type>PBL</cell_type> express high levels of <protein>Id2</protein> and no <rna>Id3 mRNA</rna> ; and with the onset of cellular proliferation , levels of <rna>Id2 mRNA</rna> decrease while levels of <rna>Id3 mRNA</rna> increase , suggesting that regulation of expression of these closely related <dna>genes</dna> is disparate .


Salicylates inhibit lipopolysaccharide-induced transcriptional activation of the tissue factor gene in human monocytic cells .

Salicylates inhibit lipopolysaccharide-induced transcriptional activation of the tissue factor gene in <cell_type>human monocytic cells</cell_type> .


Binding of plasma Factor VII/VIIa to the tissue factor ( TF ) receptor initiates the coagulation protease cascades .

Binding of <protein>plasma Factor VII/VIIa</protein> to the <protein>tissue factor ( TF ) receptor</protein> initiates the <protein>coagulation protease</protein> cascades .


TF expression by circulating monocytes is associated with thrombotic and inflammatory complications in a variety of diseases .

TF expression by <cell_type>circulating monocytes</cell_type> is associated with thrombotic and inflammatory complications in a variety of diseases .


Transcriptional activation of the human TF gene in monocytic cells exposed to bacterial lipopolysaccharide ( LPS ) is mediated by binding of c-Rel/p65 heterodimers to a kappa B site in the TF promoter .

Transcriptional activation of the <dna>human TF gene</dna> in <cell_type>monocytic cells</cell_type> exposed to bacterial lipopolysaccharide ( LPS ) is mediated by binding of <protein>c-Rel/p65 heterodimers</protein> to a <dna>kappa B site</dna> in the <dna>TF promoter</dna> .


Here , we report that a family of anti-inflammatory agents , known as the salicylates , inhibited LPS induction of TF activity and TF gene transcription in human monocytes and monocytic THP-1 cells at clinically relevant doses .

Here , we report that a family of anti-inflammatory agents , known as the salicylates , inhibited LPS induction of TF activity and <dna>TF gene</dna> transcription in <cell_type>human monocytes</cell_type> and <cell_line>monocytic THP-1 cells</cell_line> at clinically relevant doses .


Furthermore , sodium salicylate blocked the LPS-induced proteolytic degradation of I kappa B alpha , which prevented the nuclear translocation of c-Rel/p65 heterodimers .

Furthermore , sodium salicylate blocked the LPS-induced proteolytic degradation of <protein>I kappa B alpha</protein> , which prevented the nuclear translocation of <protein>c-Rel/p65 heterodimers</protein> .


In contrast , two other nonsteroidal anti-inflammatory drugs , ibuprofen and indomethacin , did not inhibit LPS induction of the TF gene .

In contrast , two other nonsteroidal anti-inflammatory drugs , ibuprofen and indomethacin , did not inhibit LPS induction of the <dna>TF gene</dna> .


These results indicated that salicylates inhibited LPS induction of TF gene transcription in monocytic cells by preventing nuclear translocation of c-Rel/p65 heterodimers .

These results indicated that salicylates inhibited LPS induction of <dna>TF gene</dna> transcription in <cell_type>monocytic cells</cell_type> by preventing nuclear translocation of <protein>c-Rel/p65 heterodimers</protein> .


The clinical benefits of salicylates in the treatment of several diseases , including atherosclerosis and rheumatoid arthritis , may be related to their ability to reduce monocyte gene expression .


Activation of the signal transducer and transcription ( STAT ) signaling pathway in a primary T cell response .

Activation of the signal transducer and transcription ( <protein>STAT</protein> ) signaling pathway in a primary T cell response .


Critical role for IL-6 .

Critical role for <protein>IL-6</protein> .


The T cell activation is initiated by interaction of specific Ags with TCR , followed by activation of intracellular biochemical events leading to activation of several genes .

The T cell activation is initiated by interaction of specific <protein>Ags</protein> with <protein>TCR</protein> , followed by activation of intracellular biochemical events leading to activation of several genes .


The activation of signal transducer and activator of transcription ( STAT ) proteins in a primary TCR -mediated activation of T cells have been explored .

The activation of signal transducer and activator of <protein>transcription ( STAT ) proteins</protein> in a primary <protein>TCR</protein> -mediated activation of <cell_type>T cells</cell_type> have been explored .


In purified human peripheral blood T cells , nuclear STAT proteins were activated approximately 3 h after activation by cross-linked anti-CD3 Abs .

In <cell_type>purified human peripheral blood T cells</cell_type> , <protein>nuclear STAT proteins</protein> were activated approximately 3 h after activation by cross-linked <protein>anti-CD3 Abs</protein> .


These STAT proteins were detected by using the IFN-gamma-activated sequence ( GAS ) and related oligonucleotides as probes in electrophoretic mobility shift assay .

These <protein>STAT proteins</protein> were detected by using the <dna>IFN-gamma-activated sequence</dna> ( <dna>GAS</dna> ) and related oligonucleotides as probes in electrophoretic mobility shift assay .


Analysis of the nuclear extracts with anti-STAT Abs indicated that they contained STAT-3 and additional proteins crossreactive with the STAT family .

Analysis of the nuclear extracts with <protein>anti-STAT Abs</protein> indicated that they contained <protein>STAT-3</protein> and additional proteins crossreactive with the <protein>STAT family</protein> .


The induction of STAT activity was inhibited completely by pretreatment with either cycloheximide or cyclosporin A , thus indicating that the induction was due to a secondary factor produced by the activated T cells .

The induction of <protein>STAT</protein> activity was inhibited completely by pretreatment with either cycloheximide or cyclosporin A , thus indicating that the induction was due to a <protein>secondary factor</protein> produced by the activated <cell_type>T cells</cell_type> .


As neutralizing anti-IL-6 Abs effectively down-regulated the early induction of STAT proteins and as exogenously added IL-6 rapidly activated DNA binding similar to TCR -mediated bindings , it can be concluded that IL-6 is the factor responsible for the activation of STAT proteins in a primary T cell response .

As <protein>neutralizing anti-IL-6 Abs</protein> effectively down-regulated the early induction of <protein>STAT proteins</protein> and as exogenously added <protein>IL-6</protein> rapidly activated DNA binding similar to <protein>TCR</protein> -mediated bindings , it can be concluded that <protein>IL-6</protein> is the factor responsible for the activation of <protein>STAT proteins</protein> in a primary T cell response .


The normal cell cycle activation program is exploited during the infection of quiescent B lymphocytes by Epstein-Barr virus .

The normal cell cycle activation program is exploited during the infection of <cell_type>quiescent B lymphocytes</cell_type> by Epstein-Barr virus .


B lymphocytes in the peripheral circulation are maintained in a non-proliferative state .

<cell_type>B lymphocytes</cell_type> in the peripheral circulation are maintained in a non-proliferative state .


Antigen recognition stimulates limited proliferation , whereas infection with Epstein-Barr virus ( EBV ) results in continual proliferation and the outgrowth of immortal cell lines .

Antigen recognition stimulates limited proliferation , whereas infection with Epstein-Barr virus ( EBV ) results in continual proliferation and the outgrowth of <cell_line>immortal cell lines</cell_line> .


Because it is not clear at which point in cell cycle the peripheral B lymphocytes are arrested , we characterized the expression of several cell cycle-associated genes in quiescent and stimulated cells .

Because it is not clear at which point in cell cycle the <cell_type>peripheral B lymphocytes</cell_type> are arrested , we characterized the expression of several <dna>cell cycle-associated genes</dna> in <cell_type>quiescent and stimulated cells</cell_type> .


We show that the expression of four cell genes , cdc-2 , cyclin E , CD23 , and cyclin D2 , are up-regulated approximately 100-fold as a result of EBV-mediated immortalization .

We show that the expression of four <dna>cell genes</dna> , <dna>cdc-2</dna> , <dna>cyclin E</dna> , <dna>CD23</dna> , and <dna>cyclin D2</dna> , are up-regulated approximately 100-fold as a result of EBV-mediated immortalization .


Because these genes play a positive role in cell proliferation , we suggest that this regulatory switch contributes to controlling entry into the cell cycle .


Transient stimulation of quiescent B lymphocytes with either a cocktail of anti-CD40 , anti-IgM , and IL4 , or EBV results in the rapid expression of the same four genes , suggesting that , after infection , EBV exploits the normal program of B-lymphocyte cell cycle activation .

Transient stimulation of <cell_type>quiescent B lymphocytes</cell_type> with either a cocktail of <protein>anti-CD40</protein> , <protein>anti-IgM</protein> , and <protein>IL4</protein> , or EBV results in the rapid expression of the same four genes , suggesting that , after infection , EBV exploits the normal program of <cell_type>B-lymphocyte</cell_type> cell cycle activation .


Expression of the chemokine receptor BLR2/EBI1 is specifically transactivated by Epstein-Barr virus nuclear antigen 2 .

Expression of the <protein>chemokine receptor</protein> <protein>BLR2/EBI1</protein> is specifically transactivated by <protein>Epstein-Barr virus nuclear antigen 2</protein> .


In our attempt to identify chemokine receptors that are related to Burkitt 's lymphoma receptor 1 ( BLR1 ) and are expressed in activated lymphocytes we used RT-PCR resulting in the isolation of a cDNA encoding a seven transmembrane receptor termed BLR2 .

In our attempt to identify <protein>chemokine receptors</protein> that are related to <protein>Burkitt 's lymphoma receptor 1</protein> ( <protein>BLR1</protein> ) and are expressed in <cell_type>activated lymphocytes</cell_type> we used RT-PCR resulting in the isolation of a cDNA encoding a <protein>seven transmembrane receptor</protein> termed <protein>BLR2</protein> .


The protein shows significant sequence similarities to the family of G-protein coupled chemokine receptors and turned out to be identical to the recently described receptor EBI1 .

The protein shows significant sequence similarities to the family of <protein>G-protein coupled chemokine receptors</protein> and turned out to be identical to the recently described <protein>receptor EBI1</protein> .


Northern blot analysis revealed that BLR2 mRNA could be highly stimulated in mitogen- and anti-CD3-treated peripheral blood lymphocytes .

Northern blot analysis revealed that <rna>BLR2 mRNA</rna> could be highly stimulated in <cell_line>mitogen- and anti-CD3-treated peripheral blood lymphocytes</cell_line> .


BLR2-specific mRNA could be detected in all Epstein-Barr virus positive B cell lines .

<rna>BLR2-specific mRNA</rna> could be detected in all <cell_line>Epstein-Barr virus positive B cell lines</cell_line> .


We show that transcription of the BLR2 gene could be specifically induced in Epstein-Barr virus negative BL 41 cells via estrogen-mediated activation of Epstein-Barr virus nuclear antigen 2 , a key regulator of viral and cellular genes in immortalized B cells .

We show that transcription of the <dna>BLR2 gene</dna> could be specifically induced in <cell_line>Epstein-Barr virus negative BL 41 cells</cell_line> via estrogen-mediated activation of <protein>Epstein-Barr virus nuclear antigen 2</protein> , a key regulator of <dna>viral and cellular genes</dna> in <cell_line>immortalized B cells</cell_line> .


Our data suggest an involvement of BLR2 in the regulation of migration in activated lymphocytes and in viral pathogenesis .

Our data suggest an involvement of <protein>BLR2</protein> in the regulation of migration in <cell_type>activated lymphocytes</cell_type> and in viral pathogenesis .


A central role for a single c-Myb binding site in a thymic locus control region .

A central role for a <dna>single c-Myb binding site</dna> in a <dna>thymic locus control region</dna> .


Locus control regions ( LCRs ) are powerful assemblies of cis elements that organize the actions of cell-type-specific trans-acting factors .

<dna>Locus control regions</dna> ( <dna>LCRs</dna> ) are powerful assemblies of <dna>cis elements</dna> that organize the actions of <protein>cell-type-specific trans-acting factors</protein> .


A 2.3-kb LCR in the human adenosine deaminase ( ADA ) gene first intron , which controls expression in thymocytes , is composed of a 200-bp enhancer domain and extended flanking sequences that facilitate activation from within chromatin .

A <protein>2.3-kb LCR</protein> in the <dna>human adenosine deaminase ( ADA ) gene first intron</dna> , which controls expression in <cell_type>thymocytes</cell_type> , is composed of a <dna>200-bp enhancer domain</dna> and extended flanking sequences that facilitate activation from within <dna>chromatin</dna> .


Prior analyses have demonstrated that the enhancer contains a 28-bp core region and local adjacent augmentative cis elements .

Prior analyses have demonstrated that the <dna>enhancer</dna> contains a <dna>28-bp core region</dna> and local adjacent augmentative <dna>cis elements</dna> .


We now show that the core contains a single critical c-Myb binding site .

We now show that the core contains a single critical <dna>c-Myb binding site</dna> .


In both transiently cotransfected human cells and stable chromatin-integrated yeast cells , c-Myb strongly transactivated reporter constructs that contained polymerized core sequences .

In both <cell_line>transiently cotransfected human cells</cell_line> and stable <cell_line>chromatin-integrated yeast cells</cell_line> , <protein>c-Myb</protein> strongly <dna>transactivated reporter constructs</dna> that contained <dna>polymerized core sequences</dna> .


c-Myb protein was strongly evident in T lymphoblasts in which the enhancer was active and was localized within discrete nuclear structures .

<protein>c-Myb protein</protein> was strongly evident in <cell_type>T lymphoblasts</cell_type> in which the <dna>enhancer</dna> was active and was localized within discrete nuclear structures .


Fetal murine thymus exhibited a striking concordance of endogenous c-myb expression with that of mouse ADA and human ADA LCR -directed transgene expression .

Fetal murine thymus exhibited a striking concordance of endogenous <dna>c-myb</dna> expression with that of <dna>mouse ADA</dna> and <dna>human ADA LCR</dna> -directed transgene expression .


Point mutation of the c-Myb site within the intact 2.3-kb LCR severely attenuated enhancer activity in transfections and LCR activity in transgenic thymocytes .

Point mutation of the <dna>c-Myb site</dna> within the intact <protein>2.3-kb LCR</protein> severely attenuated enhancer activity in transfections and <dna>LCR</dna> activity in <cell_line>transgenic thymocytes</cell_line> .


Within the context of a complex enhancer and LCR , c-Myb can act as an organizer of thymocyte-specific gene expression via a single binding site .

Within the context of a <dna>complex enhancer</dna> and <dna>LCR</dna> , <protein>c-Myb</protein> can act as an organizer of <dna>thymocyte-specific gene</dna> expression via a single binding site .


A regulatory element in the human interleukin 2 gene promoter is a binding site for the zinc finger proteins Sp1 and EGR-1 .

A <dna>regulatory element</dna> in the <dna>human interleukin 2 gene promoter</dna> is a <dna>binding site</dna> for the <protein>zinc finger proteins</protein> <protein>Sp1</protein> and <protein>EGR-1</protein> .


Activation of the interleukin 2 ( IL-2 ) gene after antigen recognition is a critical event for T cell proliferation and effector function .

Activation of the <dna>interleukin 2 ( IL-2 ) gene</dna> after antigen recognition is a critical event for T cell proliferation and effector function .


Prior studies have identified several transcription factors that contribute to the activity of the IL-2 promoter in stimulated T lymphocytes .

Prior studies have identified several <protein>transcription factors</protein> that contribute to the activity of the <dna>IL-2 promoter</dna> in <cell_type>stimulated T lymphocytes</cell_type> .


Here we describe a novel regulatory element within the IL-2 promoter located immediately upstream of the nuclear factor of activated T cell ( NFAT ) domain .

Here we describe a novel <dna>regulatory element</dna> within the <dna>IL-2 promoter</dna> located immediately upstream of the <dna>nuclear factor of activated T cell ( NFAT ) domain</dna> .


This region ( termed the zinc finger protein binding region ( ZIP ) ) serves as binding site for two differently regulated zinc finger proteins : the constitutively expressed transcription factor Sp1 and the inducible early growth response protein EGR-1 .

This region ( termed the <dna>zinc finger protein binding region</dna> ( <dna>ZIP</dna> ) ) serves as binding site for two differently regulated <protein>zinc finger proteins</protein> : the <protein>constitutively expressed transcription factor</protein> <protein>Sp1</protein> and the <protein>inducible early growth response protein</protein> <protein>EGR-1</protein> .


In unstimulated cells which do not secrete IL-2 , only Sp1 binds to this region , while in stimulated IL-2 secreting cells the inducible EGR-1 protein recognizes this element .

In <cell_type>unstimulated cells</cell_type> which do not secrete <protein>IL-2</protein> , only <protein>Sp1</protein> binds to this region , while in <cell_line>stimulated IL-2 secreting cells</cell_line> the <protein>inducible EGR-1 protein</protein> recognizes this element .


In Jurkat T cells , the ZIP site serves as an activator for IL-2 gene expression , and a combination of ZIP and NFAT binding sites is required for maximal IL-2 promoter activity .

In <cell_line>Jurkat T cells</cell_line> , the <dna>ZIP site</dna> serves as an activator for <protein>IL-2</protein> gene expression , and a combination of <dna>ZIP</dna> and <dna>NFAT binding sites</dna> is required for maximal <dna>IL-2 promoter</dna> activity .


These results suggest a critical role of the ZIP site for IL-2 promoter activity .

These results suggest a critical role of the <dna>ZIP site</dna> for <dna>IL-2 promoter</dna> activity .


Activation of the HIV-1 enhancer by the LEF-1 HMG protein on nucleosome-assembled DNA in vitro .

Activation of the <dna>HIV-1 enhancer</dna> by the <protein>LEF-1 HMG protein</protein> on <dna>nucleosome-assembled DNA</dna> in vitro .


Lymphoid enhancer-binding factor 1 ( LEF-1 ) is a regulatory high mobility group ( HMG ) protein that activates the T cell receptor alpha ( TCR alpha ) enhancer in a context-restricted manner in T cells .

<protein>Lymphoid enhancer-binding factor 1</protein> ( <protein>LEF-1</protein> ) is a <protein>regulatory high mobility group ( HMG ) protein</protein> that activates the <dna>T cell receptor alpha ( TCR alpha ) enhancer</dna> in a context-restricted manner in <cell_type>T cells</cell_type> .


In this paper we demonstrate that the distal region of the human immunodeficiency virus-1 ( HIV-1 ) enhancer , which contains DNA-binding sites for LEF-1 and Ets-1 , also provides a functional context for activation by LEF-1 .

In this paper we demonstrate that the distal region of the <dna>human immunodeficiency virus-1 ( HIV-1 ) enhancer</dna> , which contains <dna>DNA-binding sites</dna> for <protein>LEF-1</protein> and Ets-1 , also provides a functional context for activation by <protein>LEF-1</protein> .


First , we show that mutations in the LEF-1-binding site inhibit the activity of multimerized copies of the HIV-1 enhancer in Jurkat T cells , and that LEF-1/GAL4 can activate a GAL4-substituted HIV-1 enhancer 80- to 100-fold in vivo .

First , we show that mutations in the <dna>LEF-1-binding site</dna> inhibit the activity of <dna>multimerized copies</dna> of the <dna>HIV-1 enhancer</dna> in <cell_line>Jurkat T cells</cell_line> , and that <protein>LEF-1/GAL4</protein> can activate a <dna>GAL4-substituted HIV-1 enhancer</dna> 80- to 100-fold in vivo .


Second , recombinant LEF-1 is shown to activate HIV-1 transcription on chromatin-assembled DNA in vitro .

Second , <protein>recombinant LEF-1</protein> is shown to activate HIV-1 transcription on <dna>chromatin-assembled DNA</dna> in vitro .


By using a nucleosome -assembly system derived from Drosophila embryos , we find that the packaging of DNA into chromatin in vitro strongly represses HIV-1 transcription and that repression can be counteracted efficiently by preincubation of the DNA with LEF-1 ( or LEF-1 and Ets-1 ) supplemented with fractions containing the promoter-binding protein , Sp1 .

By using a <protein>nucleosome</protein> -assembly system derived from Drosophila embryos , we find that the packaging of DNA into <dna>chromatin</dna> in vitro strongly represses HIV-1 transcription and that repression can be counteracted efficiently by preincubation of the DNA with <protein>LEF-1</protein> ( or <protein>LEF-1</protein> and <protein>Ets-1</protein> ) supplemented with fractions containing the <protein>promoter-binding protein</protein> , <protein>Sp1</protein> .


Addition of TFE-3 , which binds to an E-box motif upstream of the LEF-1 and Ets-1 sites , further augments transcription in this system .

Addition of <protein>TFE-3</protein> , which binds to an <dna>E-box motif</dna> upstream of the <dna>LEF-1 and Ets-1 sites</dna> , further augments transcription in this system .


Individually or collectively , none of the three enhancer-binding proteins ( LEF-1 , Ets-1 , and TFE-3 ) could activate transcription in the absence of Sp1 .

Individually or collectively , none of the three <protein>enhancer-binding proteins</protein> ( <protein>LEF-1</protein> , <protein>Ets-1</protein> , and <protein>TFE-3</protein> ) could activate transcription in the absence of <protein>Sp1</protein> .


A truncation mutant of LEF-1 ( HMG-88 ) , which contains the HMG box but lacks the trans-activation domain , did not activate transcription from nucleosomal DNA , indicating that bending of DNA by the HMG domain is not sufficient to activate transcription in vitro .

A <protein>truncation mutant</protein> of <protein>LEF-1</protein> ( <protein>HMG-88</protein> ) , which contains the <protein>HMG box</protein> but lacks the <protein>trans-activation domain</protein> , did not activate transcription from <dna>nucleosomal DNA</dna> , indicating that bending of DNA by the <protein>HMG domain</protein> is not sufficient to activate transcription in vitro .


We conclude that transcription activation by LEF-1 in vitro is a chromatin -dependent process that requires a functional trans-activation domain in addition to the HMG domain .

We conclude that transcription activation by <protein>LEF-1</protein> in vitro is a <dna>chromatin</dna> -dependent process that requires a functional <protein>trans-activation domain</protein> in addition to the <protein>HMG domain</protein> .


HIV-1 envelope glycoproteins induce activation of activated protein-1 in CD4+ T cells [ published erratum appears in J Biol Chem 1995 Dec 1 ; 270 ( 48 ) : 29038 ]

<protein>HIV-1 envelope glycoproteins</protein> induce activation of activated <protein>protein-1</protein> in <cell_type>CD4+ T cells</cell_type> [ published erratum appears in J Biol Chem 1995 Dec 1 ; 270 ( 48 ) : 29038 ]


Activation of CD4 positive T cells is a primary requirement for human immunodeficiency virus ( HIV ) entry , efficient HIV replication , and progression to AIDS , Utilizing CD4 positive T cell lines and purified T cells from normal individuals , we have demonstrated that native envelope glycoproteins of HIV , gp 160 , can induce activation of transcription factor , activated protein-1 ( AP-1 ) .

Activation of <cell_type>CD4 positive T cells</cell_type> is a primary requirement for human immunodeficiency virus ( HIV ) entry , efficient HIV replication , and progression to AIDS , Utilizing <cell_line>CD4 positive T cell lines</cell_line> and <cell_type>purified T cells</cell_type> from normal individuals , we have demonstrated that <protein>native envelope glycoproteins</protein> of HIV , <protein>gp 160</protein> , can induce activation of <protein>transcription factor , activated protein-1</protein> ( <protein>AP-1</protein> ) .


The stimulatory effects of gp160 are mediated through the CD4 molecule , since treatment of gp160 with soluble CD4-IgG abrogates its activity , and CD4 negative T cell lines fail to be stimulated with gp160 .

The stimulatory effects of <protein>gp160</protein> are mediated through the <protein>CD4 molecule</protein> , since treatment of <protein>gp160</protein> with soluble <protein>CD4-IgG</protein> abrogates its activity , and <cell_line>CD4 negative T cell lines</cell_line> fail to be stimulated with <protein>gp160</protein> .


Immunoprecipitation of the gp 160 -induced nuclear extracts with polyclonal antibodies to Fos and Jun proteins indicates that AP-1 complex is comprised of members of these family of proteins .

Immunoprecipitation of the <protein>gp 160</protein> -induced nuclear extracts with <protein>polyclonal antibodies</protein> to <protein>Fos</protein> and <protein>Jun proteins</protein> indicates that <protein>AP-1 complex</protein> is comprised of members of these family of proteins .


The gp160-induced AP-1 complex is dependent upon protein tyrosine phosphorylation and is protein synthesis-independent .

The <protein>gp160-induced AP-1 complex</protein> is dependent upon protein tyrosine phosphorylation and is protein synthesis-independent .


This stimulation can also be abolished by inhibitors of protein kinase C , but it is unaffected by calcium channel blocker or cyclosporine A .

This stimulation can also be abolished by inhibitors of <protein>protein kinase C</protein> , but it is unaffected by calcium channel blocker or cyclosporine A .


This gp160 treatment adversely affects the functional capabilities of T cells : pre-treatment of CD4+ T cells with gp160 for 4 h at 37 degrees C inhibited anti-CD3 -induced interleukin-2 secretion .

This <protein>gp160</protein> treatment adversely affects the functional capabilities of <cell_type>T cells</cell_type> : pre-treatment of <cell_type>CD4+ T cells</cell_type> with <protein>gp160</protein> for 4 h at 37 degrees C inhibited <protein>anti-CD3</protein> -induced <protein>interleukin-2</protein> secretion .


Effects similar to gp160 were seen with anti-CD4 mAb .

Effects similar to <protein>gp160</protein> were seen with <protein>anti-CD4 mAb</protein> .


The aberrant activation of AP-1 by gp160 in CD4 positive T cells could result in up-regulation of cytokines containing AP-1 sites , e.g . interleukin-3 and granulocyte macrophage colony-stimulating factor , and concurrently lead to T cell unresponsiveness by inhibiting interleukin-2 secretion .

The aberrant activation of <protein>AP-1</protein> by <protein>gp160</protein> in <cell_type>CD4 positive T cells</cell_type> could result in up-regulation of <protein>cytokines</protein> containing <dna>AP-1 sites</dna> , e.g . <protein>interleukin-3</protein> and <protein>granulocyte macrophage colony-stimulating factor</protein> , and concurrently lead to <cell_type>T cell</cell_type> unresponsiveness by inhibiting <protein>interleukin-2</protein> secretion .