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Based on the sequence and mechanism of TATA box initiation, mutations such as insertions, deletions, and point mutations to this consensus sequence can result in phenotypic changes. These phenotypic changes can then turn into a disease phenotype. Some diseases associated with mutations in the TATA box include gastric cancer, spinocerebellar ataxia, Huntington's disease, blindness, β-thalassemia, immunosuppression, Gilbert's syndrome, and HIV-1. The TATA-binding protein (TBP) could also be targeted by viruses as a means of viral transcription. | https://en.wikipedia.org/wiki/Hogness_box |
In molecular biology, the Tymovirus coat protein refers to the protein coat of a virus order, named Tymovirales. More specifically this protein signature is found only in coat proteins from the related tymoviruses. The coat protein (CP) is also known as the virion protein. The virus coat is composed of 180 copies of the coat protein arranged in an icosahedral shell. | https://en.wikipedia.org/wiki/Tymovirus_coat_protein |
In molecular biology, the UBX protein domain is found in ubiquitin-regulatory proteins, which are members of the ubiquitination pathway, as well as a number of other ubiquitin-like proteins including FAF-1 (FAS-associated factor 1), the human Rep-8 reproduction protein and several hypothetical proteins from yeast. The function of the UBX domain is not known although the fragment of avian FAF-1 containing the UBX domain causes apoptosis of transfected cells. | https://en.wikipedia.org/wiki/UBX_protein_domain |
In molecular biology, the Ubiquitin-Interacting Motif (UIM), or 'LALAL-motif', is a sequence motif of about 20 amino acid residues, which was first described in the 26S proteasome subunit PSD4/RPN-10 that is known to recognise ubiquitin. In addition, the UIM is found, often in tandem or triplet arrays, in a variety of proteins either involved in ubiquitination and ubiquitin metabolism, or known to interact with ubiquitin-like modifiers. Among the UIM proteins are two different subgroups of the UBP (ubiquitin carboxy-terminal hydrolase) family of deubiquitinating enzymes, one F-box protein, one family of HECT-containing ubiquitin-ligases (E3s) from plants, and several proteins containing ubiquitin-associated UBA and/or UBX domains. In most of these proteins, the UIM occurs in multiple copies and in association with other domains such as UBA (INTERPRO), UBX (INTERPRO), ENTH domain, EH (INTERPRO), VHS (INTERPRO), SH3 domain, HECT, VWFA (INTERPRO), EF-hand calcium-binding, WD-40, F-box (INTERPRO), LIM, protein kinase, ankyrin, PX, phosphatidylinositol 3- and 4-kinase (INTERPRO), C2 domain, OTU (INTERPRO), DnaJ domain (INTERPRO), RING-finger (INTERPRO) or FYVE-finger (INTERPRO). | https://en.wikipedia.org/wiki/Ubiquitin-interacting_motif |
UIMs have been shown to bind ubiquitin and to serve as a specific targeting signal important for monoubiquitination. Thus, UIMs may have several functions in ubiquitin metabolism each of which may require different numbers of UIMs.The UIM is unlikely to form an independent protein domain. Instead, based on the spacing of the conserved residues, the motif probably forms a short alpha-helix that can be embedded into different protein folds. | https://en.wikipedia.org/wiki/Ubiquitin-interacting_motif |
Some proteins known to contain an UIM are listed below: Eukaryotic PSD4/RPN-10/S5, a multi-ubiquitin binding subunit of the 26S proteasome. Vertebrate Machado-Joseph disease protein 1 (Ataxin-3), which acts as a histone-binding protein that regulates transcription; defects in Ataxin-3 cause the neurodegenerative disorder Machado-Joseph disease (MJD). Vertebrate epsin and epsin2. | https://en.wikipedia.org/wiki/Ubiquitin-interacting_motif |
Vertebrate hepatocyte growth factor-regulated tyrosine kinase substrate (HRS). Mammalian epidermal growth factor receptor substrate 15 (EPS15), which is involved in cell growth regulation. Mammalian epidermal growth factor receptor substrate EPS15R. | https://en.wikipedia.org/wiki/Ubiquitin-interacting_motif |
Drosophila melanogaster (Fruit fly) liquid facets (lqf), an epsin. Yeast VPS27 vacuolar sorting protein, which is required for membrane traffic to the vacuole. == References == | https://en.wikipedia.org/wiki/Ubiquitin-interacting_motif |
In molecular biology, the VHS protein domain is approximately 140 residues long. Its name is an acronym derived from its occurrence in VPS-27, Hrs and STAM. It is a domain commonly found in the N-terminus of many proteins. | https://en.wikipedia.org/wiki/VHS_protein_domain |
In molecular biology, the WAC domain is a protein domain found on the N-terminus of WSTF protein. Its function is still unknown, but putatively thought to be involved in cell growth. The protein domain has been found to be present in both prokaryotes and eukaryotes | https://en.wikipedia.org/wiki/WAC_protein_domain |
In molecular biology, the Whey acidic proteins (WAP) have been identified as a major whey protein family in milk, and are important in regulating the proliferation of mammary epithelial cells. Additionally, their physiological function is thought to be similar to a protease inhibitor. It has been concluded, therefore, that WAP regulate the proliferation of mammary epithelial cells by preventing elastase-type serine proteases from carrying out laminin degradation and by suppressing the MAP kinase signal pathway in the cell cycle. | https://en.wikipedia.org/wiki/Whey_acidic_protein |
In molecular biology, the X8 domain, is thought to play a role in targeting the plasmodesmata by providing it with structural support. The domain is able to do this since it contains signal sequences for a glycosylphosphatidylinositol (GPI) linkage to the extracellular face of the plasma membrane. This domain is involved in carbohydrate binding. | https://en.wikipedia.org/wiki/X8_protein_domain |
In molecular biology, the XPC binding domain is thought to play a role in DNA damage discrimination and in the enhancement of cell survival. They bind specifically and directly to the xeroderma pigmentosum group C protein (XPC) to initiate nucleotide excision repair (NER). Members of this entry adopt a structure consisting of four alpha helices, arranged in an array. == References == | https://en.wikipedia.org/wiki/XPC-binding |
In molecular biology, the XPG-I is a protein domain found on Xeroderma Pigmentosum Complementation Group G (XPG) protein. The XPG protein is an endonuclease which repairs DNA damage caused by ultraviolet light (UV light). The XPG protein repairs DNA by a process called, Nucleotide excision repair. Mutations in the protein commonly cause Xeroderma Pigmentosum which often lead to skin cancer. | https://en.wikipedia.org/wiki/XPG_I_protein_domain |
In molecular biology, the YEATS domain is a protein domain found in a variety of proteins from eukaryotic organisms. YEATS domain proteins are found in a variety of chromatin modification molecular complexes. Structurally the domain has an immunoglobulin like fold. The YEATS domain has shown to bind to acetyllysine protein modifications. In addition to lysine acetylation, the YEATS domain has shown to be a reader domain for various lysine acylations, with highest affinity for lysine crotonylation. | https://en.wikipedia.org/wiki/YEATS_domain |
In molecular biology, the Ycf4 protein is involved in the assembly of the photosystem I complex which is part of an energy-harvesting process named photosynthesis. Without Ycf4, photosynthesis would be inefficient affecting plant growth. Ycf4 is located in the thylakoid membrane of the chloroplast. Ycf4 is important for the light dependent reaction of photosynthesis. | https://en.wikipedia.org/wiki/Ycf4_protein_domain |
To date, three thylakoid proteins involved in the stable accumulation of PSI have been identified, these are as follows: BtpA (INTERPRO), Ycf3 Ycf4.The Ycf4 protein is firmly associated with the thylakoid membrane, presumably through a transmembrane domain. Ycf4 co-fractionates with a protein complex larger than PSI upon sucrose density gradient centrifugation of solubilised thylakoids.Ycf is an acronym standing for hypothetical chloroplast open reading frame. == References == | https://en.wikipedia.org/wiki/Ycf4_protein_domain |
In molecular biology, the Ydc2 domains are enzymes, or in other words biological catalysts, capable of resolving Holliday junctions into separate DNA duplexes by cleaving DNA after 5'-CT-3, and 5'-TT-3, sequences. | https://en.wikipedia.org/wiki/Ydc2_protein_domain |
In molecular biology, the YjeF N terminal is a protein domain found in the N-terminal of the protein, EDC3. The YjeF N-terminal domains occur either as single proteins or fusions with other domains and are commonly associated with enzymes. They help assemble the processing body (P-body) in preparation for mRNAdecay. Structural homology indicated it may have some similarity to the enzyme family, hydrolase. | https://en.wikipedia.org/wiki/YjeF_N_terminal_protein_domain |
In molecular biology, the YqaJ refers to the YqaJ/K domain from the skin prophage of the bacterium, Bacillus subtilis. This protein domain, often found in bacterial species, is actually of viral origin. The protein forms an oligomer and functions as an alkaline exonuclease, or in simpler terms, an enzyme that digests double-stranded DNA. It is a reaction which is dependent on Magnesium. It has a preference for 5'-phosphorylated DNA ends. It thus forms part of the two-component SynExo viral recombinase functional unit. | https://en.wikipedia.org/wiki/YqaJ_protein_domain |
In molecular biology, the adaptor complexes medium subunit domain is a protein domain found at the C-terminus of the mu subunit from various clathrin adaptor protein complexes (AP1, AP2, AP3, AP4 and AP5) and muniscins. The C-terminal domain has an immunoglobulin-like beta-sandwich fold consisting of 9 strands in 2 sheets with a Greek key topology, similar to that found in cytochrome f and certain transcription factors. The mu subunit regulates the coupling of clathrin lattices with particular membrane proteins by self-phosphorylation via a mechanism that is still unclear. The mu subunit possesses a highly conserved N-terminal domain of around 230 amino acids, which may be the region of interaction with other AP proteins; a linker region of between 10 and 42 amino acids; and a less well-conserved C-terminal domain of around 190 amino acids, which may be the site of specific interaction with the protein being transported in the vesicle. | https://en.wikipedia.org/wiki/Adaptor_complexes_medium_subunit_domain |
In molecular biology, the adhesin molecule (immunoglobulin-like) is a protein domain. This domain is found in mucosal vascular addressin cell adhesion molecule 1 proteins (MAdCAM-1). These are cell adhesion molecules expressed on the endothelium in mucosa that guide the specific homing of lymphocytes into mucosal tissues. MAdCAM-1 belongs to a subclass of the immunoglobulin superfamily (IgSF), the members of which are ligands for integrins. The crystal structure of this domain has been reported; it adopts an immunoglobulin-like beta-sandwich structure, with seven strands arranged in two beta-sheets in a Greek-key topology. | https://en.wikipedia.org/wiki/Adhesion_molecule_(immunoglobulin-like) |
In molecular biology, the amino acid kinase domain is a protein domain. It is found in protein kinases with various specificities, including the aspartate, glutamate and uridylate kinase families. In prokaryotes and plants the synthesis of the essential amino acids lysine and threonine is predominantly regulated by feed-back inhibition of aspartate kinase (AK) and dihydrodipicolinate synthase (DHPS). In Escherichia coli, thrA, metLM, and lysC encode aspartokinase isozymes that show feedback inhibition by threonine, methionine, and lysine, respectively. | https://en.wikipedia.org/wiki/Amino_acid_kinase |
The lysine-sensitive isoenzyme of aspartate kinase from spinach leaves has a subunit composition of 4 large and 4 small subunits.In plants although the control of carbon fixation and nitrogen assimilation has been studied in detail, relatively little is known about the regulation of carbon and nitrogen flow into amino acids. The metabolic regulation of expression of an Arabidopsis thaliana aspartate kinase/homoserine dehydrogenase (AK/HSD) gene, which encodes two linked key enzymes in the biosynthetic pathway of aspartate family amino acids has been studied. The conversion of aspartate into either the storage amino acid asparagine or aspartate family amino acids may be subject to a coordinated, reciprocal metabolic control, and this biochemical branch point is a part of a larger, coordinated regulatory mechanism of nitrogen and carbon storage and utilization. == References == | https://en.wikipedia.org/wiki/Amino_acid_kinase |
In molecular biology, the amylin protein family or calcitonin/CGRP/IAPP protein family is a family of proteins, which includes the precursors of calcitonin/calcitonin gene-related peptide (CGRP), islet amyloid polypeptide (IAPP) and adrenomedullin. Calcitonin is a 32 amino acid polypeptide hormone that causes a rapid but short-lived drop in the level of calcium and phosphate in the blood, by promoting the incorporation of these ions in the bones, alpha type. Alternative splicing of the gene coding for calcitonin produces a distantly related peptide of 37 amino acids, called calcitonin gene-related peptide (CGRP), beta type. CGRP induces vasodilatation in a variety of vessels, including the coronary, cerebral and systemic vasculature. | https://en.wikipedia.org/wiki/Calcitonin-like_protein_family |
Its abundance in the CNS also points toward a neurotransmitter or neuromodulator role. Islet amyloid polypeptide (IAPP) (also known as diabetes-associated peptide (DAP), or amylin) is a peptide of 37 amino acids that selectively inhibits insulin-stimulated glucose utilization and glycogen deposition in muscle, while not affecting adipocyte glucose metabolism. Structurally, IAPP is closely related to CGRP. | https://en.wikipedia.org/wiki/Calcitonin-like_protein_family |
Two conserved cysteines in the N-terminal of these peptides are known to be involved in a disulfide bond. The C-terminal amino acid of all three peptides is amidated. xCxxxxxCxxxxxxxxxxxxxxxxxxxxxxxxxxxx-NH(2) | | Amide group +-----+ | https://en.wikipedia.org/wiki/Calcitonin-like_protein_family |
In molecular biology, the ankyrin-G binding motif of KCNQ2-3 is a protein motif found in the potassium channels KCNQ2 and KCNQ3. Interactions with ankyrin-G (ankyrin-3) are crucial to the localisation of voltage-gated sodium channels (VGSCs) at the axonal initial segment and for neurons to initiate action potentials. This conserved 9-amino acid motif ((V/A)P(I/L)AXXE(S/D)D) is required for ankyrin-G binding and functions to localise sodium channels to a variety of 'excitable' membrane domains both inside and outside of the nervous system. This motif has also been identified in the potassium channel 6TM proteins KCNQ2 and KCNQ3 that correspond to the M channels that exert a crucial influence over neuronal excitability. | https://en.wikipedia.org/wiki/Ankyrin-G_binding_motif_of_KCNQ2-3 |
KCNQ2/KCNQ3 channels are preferentially localised to the surface of axons both at the axonal initial segment and more distally, and this axonal initial segment targeting of surface KCNQ channels is mediated by these ankyrin-G binding motifs of KCNQ2 and KCNQ3. KCNQ3 is a major determinant of M channel localisation to the AIS, rather than KCNQ2. Phylogenetic analysis reveals that anchor motifs evolved sequentially in chordates (NaV channel) and jawed vertebrates (KCNQ2/3). == References == | https://en.wikipedia.org/wiki/Ankyrin-G_binding_motif_of_KCNQ2-3 |
In molecular biology, the apolipophorin III family of proteins are a family of exchangeable apolipoproteins. Exchangeable apolipoproteins constitute a functionally important family of proteins that play critical roles in lipid transport and lipoprotein metabolism. Apolipophorin III (apoLp-III) is a prototypical exchangeable apolipoprotein found in many insect species that functions in transport of diacylglycerol (DAG) from the fat body lipid storage depot to flight muscles in the adult life stage. The special lipoproteins they form are called lipophorins. == References == | https://en.wikipedia.org/wiki/Apolipophorin_III |
In molecular biology, the archease' superfamily of proteins are represented in all three domains of life. Archease genes are generally located adjacent to genes encoding proteins involved in DNA or RNA processing and therefore been predicted to be modulators or chaperones involved in DNA or RNA metabolism. Many of the roles of archeases remain to be established experimentally. The function of one of the archeases from the hyperthermophile Pyrococcus abyssi has been determined. | https://en.wikipedia.org/wiki/Archease |
The gene encoding the archease (PAB1946) is located in a bicistronic operon immediately upstream from a second open reading frame (PAB1947), which encodes a tRNA m5C methyltransferase. The methyl transferase catalyses m5C formation at several cytosine's within tRNAs with preference for C49; the specificity of the methyltransferase reaction being increased by the archease. | https://en.wikipedia.org/wiki/Archease |
The archease exists in monomeric and oligomeric states, with only the oligomeric forms able to bind the methyltransferase. Binding prevents aggregation and hinders dimerisation of the methyltransferase-tRNA complex.The function of this family of archeases as chaperones is supported by structural analysis of the archease from Methanobacterium thermoautotrophicum, which shows homology to heat shock protein 33, a chaperone protein that inhibits the aggregation of partially denatured proteins. == References == | https://en.wikipedia.org/wiki/Archease |
In molecular biology, the arginine repressor (ArgR) is a repressor of prokaryotic arginine deiminase pathways. The arginine dihydrolase (AD) pathway is found in many prokaryotes and some eukaryotes, an example of the latter being Giardia lamblia (Giardia intestinalis). The three-enzyme anaerobic pathway breaks down L-arginine to form 1 mol of ATP, carbon dioxide and ammonia. In some bacteria, the first enzyme, arginine deiminase, can account for up to 10% of total cell protein.Most prokaryotic arginine deiminase pathways are under the control of a repressor gene, termed ArgR. | https://en.wikipedia.org/wiki/Arginine_repressor_ArgR |
This is a negative regulator, and will only release the arginine deiminase operon for expression in the presence of arginine. The crystal structure of apo-ArgR from Bacillus stearothermophilus has been determined to 2.5A by means of X-ray crystallography. The protein exists as a hexamer of identical subunits, and is shown to have six DNA-binding domains, clustered around a central oligomeric core when bound to arginine. | https://en.wikipedia.org/wiki/Arginine_repressor_ArgR |
It predominantly interacts with A.T residues in ARG boxes. This hexameric protein binds DNA at its N terminus to repress arginine biosynthesis or activate arginine catabolism. | https://en.wikipedia.org/wiki/Arginine_repressor_ArgR |
Some species have several ArgR paralogs. In a neighbour-joining tree, some of these paralogous sequences show long branches and differ significantly from the well-conserved C-terminal region. == References == | https://en.wikipedia.org/wiki/Arginine_repressor_ArgR |
In molecular biology, the ars operon is an operon found in several bacterial taxon. It is required for the detoxification of arsenate, arsenite, and antimonite. This system transports arsenite and antimonite out of the cell. The pump is composed of two polypeptides, the products of the arsA and arsB genes. | https://en.wikipedia.org/wiki/Ars_operon |
This two-subunit enzyme produces resistance to arsenite and antimonite. Arsenate, however, must first be reduced to arsenite before it is extruded. A third gene, arsC, expands the substrate specificity to allow for arsenate pumping and resistance. | https://en.wikipedia.org/wiki/Ars_operon |
ArsC is an approximately 150-residue arsenate reductase that uses reduced glutathione (GSH) to convert arsenate to arsenite with a redox active cysteine residue in the active site. ArsC forms an active quaternary complex with GSH, arsenate, and glutaredoxin 1 (Grx1). The three ligands must be present simultaneously for reduction to occur. | https://en.wikipedia.org/wiki/Ars_operon |
In molecular biology, the auxin binding protein family is a family of proteins which bind auxin. They are located in the lumen of the endoplasmic reticulum (ER). The primary structure of these proteins contains an N-terminal hydrophobic leader sequence of 30-40 amino acids, which could represent a signal for translocation of the protein to the ER. The mature protein comprises around 165 residues, and contains a number of potential N-glycosylation sites. | https://en.wikipedia.org/wiki/Auxin_binding_protein |
In vitro transport studies have demonstrated co-translational glycosylation. Retention within the lumen of the ER correlates with an additional signal located at the C terminus, represented by the sequence Lys-Asp-Glu-Leu, known to be responsible for preventing secretion of proteins from the lumen of the ER in eukaryotic cells. == References == | https://en.wikipedia.org/wiki/Auxin_binding_protein |
In molecular biology, the barwin domain is a protein domain found in barwin ("barley wound-induced"), a basic protein isolated from aqueous extracts of barley seeds. Barwin is 125 amino acids in length, and contains six cysteine residues that combine to form three disulphide bridges. In the pathogenesis-related protein nomenclature, it is PR-4. | https://en.wikipedia.org/wiki/Barwin_domain |
This domain is found in a 122 amino acid stretch in the C-terminal of the products of two wound-induced genes (win1 and win2; P09761, P09762) from potato, the product of the Pro-hevein gene of rubber trees, and pathogenesis-related protein 4 from tobacco (P29062, P29063). The high levels of similarity among these proteins, and their ability to bind saccharides, suggest that the barwin domain may be involved in a common defence mechanism in plants. == References == | https://en.wikipedia.org/wiki/Barwin_domain |
In molecular biology, the cache domain is an extracellular protein domain that is predicted to have a role in small-molecule recognition in a wide range of proteins, including the animal dihydropyridine-sensitive voltage-gated Ca2+ channel alpha-2delta subunit, and various bacterial chemotaxis receptors. The name Cache comes from CAlcium channels and CHEmotaxis receptors. This domain consists of an N-terminal part with three predicted strands and an alpha-helix, and a C-terminal part with a strand dyad followed by a relatively unstructured region. The N-terminal portion of the (unpermuted) Cache domain contains three predicted strands that could form a sheet analogous to that present in the core of the PAS domain structure. | https://en.wikipedia.org/wiki/Cache_domain |
Cache domains are particularly widespread in bacteria such as Vibrio cholerae. The animal calcium channel alpha-2delta subunits might have acquired a part of their extracellular domains from a bacterial source. The Cache domain appears to have arisen from the GAF-PAS fold despite their divergent functions. == References == | https://en.wikipedia.org/wiki/Cache_domain |
In molecular biology, the cadherin cytoplasmic region is a conserved region found at the C-terminus of cadherin proteins. A key determinant to the strength of the binding that it is mediated by cadherins is the juxtamembrane region (the part of the cytoplasmic region which is adjacent to the transmembrane domain) of the cadherin. This region induces clustering and also binds to the protein catenin (p120ctn). The cytoplasmic region is highly conserved in sequence and has been shown experimentally to regulate the cell-cell binding function of the extracellular domain of E-cadherin, possibly through interaction with the cytoskeleton. | https://en.wikipedia.org/wiki/Cadherin_cytoplasmic_region |
In molecular biology, the calcipressin family of proteins negatively regulate calcineurin by direct binding. They are essential for the survival of T helper type 1 cells. Calcipressin 1 is a phosphoprotein that increases its capacity to inhibit calcineurin when phosphorylated at the conserved FLISPP motif; this phosphorylation also controls the half-life of calcipressin 1 by accelerating its degradation.In humans, the Calcipressins family of proteins is derived from three genes. Calcipressin 1 is also known as modulatory calcineurin-interacting protein 1 (MCIP1), Adapt78 and Down syndrome critical region 1 (DSCR1). | https://en.wikipedia.org/wiki/Calcipressin |
Calcipressin 2 is variously known as MCIP2, ZAKI-4 and DSCR1-like 1. Calcipressin 3 is also called MCIP3 and DSCR1-like 2. == References == | https://en.wikipedia.org/wiki/Calcipressin |
In molecular biology, the calcium-activated potassium channel beta subunit is a family of proteins comprising the beta subunits of calcium-activated potassium channels. The functional diversity of potassium channels can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. The beta subunit (which is thought to possess 2 transmembrane domains) increases the calcium sensitivity of the BK channel. | https://en.wikipedia.org/wiki/Calcium-activated_potassium_channel_beta_subunit |
It does this by enhancing the time spent by the channel in burst-like open states. However, it has little effect on the durations of closed intervals between bursts, or on the numbers of open and closed states entered during gating. == References == | https://en.wikipedia.org/wiki/Calcium-activated_potassium_channel_beta_subunit |
In molecular biology, the calcium-binding EGF domain is an EGF-like domain of about forty amino-acid residues found in epidermal growth factor (EGF). This domain is present in a large number of membrane-bound and extracellular, mostly animal, proteins. Many of these proteins require calcium for their biological function and a calcium-binding site has been found at the N-terminus of some EGF-like domains. Calcium-binding may be crucial for numerous protein-protein interactions. | https://en.wikipedia.org/wiki/Calcium-binding_EGF_domain |
For human coagulation factor IX it has been shown that the calcium-ligands form a pentagonal bipyramid. The first, third and fourth conserved negatively charged or polar residues are side chain ligands. The latter is possibly hydroxylated. | https://en.wikipedia.org/wiki/Calcium-binding_EGF_domain |
A conserved aromatic residue, as well as the second conserved negative residue, are thought to be involved in stabilising the calcium-binding site. As in non-calcium binding EGF-like domains, there are six conserved cysteines and the structure of both types is very similar as calcium-binding induces only strictly local structural changes. == References == | https://en.wikipedia.org/wiki/Calcium-binding_EGF_domain |
In molecular biology, the calmodulin-regulated spectrin-associated CKK domain (also known as the CKK domain) is a domain which occurs at the C-terminus of a family of eumetazoan proteins collectively defined as calmodulin-regulated spectrin-associated, or CAMSAP, proteins. CAMSAP proteins carry an N-terminal region that includes the CH domain, a central region including a predicted coiled-coil and this C-terminal. This domain is the part of the CAMSAP proteins that binds to microtubules. The domain appears to act by producing inhibition of neurite extension, probably by blocking microtubule function. | https://en.wikipedia.org/wiki/Calmodulin-regulated_spectrin-associated_CKK_domain |
CKK represents a domain that has evolved with the metazoa. The structure of this domain in murine hypothetical protein has shown the domain to adopt a mainly beta barrel structure with an associated alpha-helical hairpin. == References == | https://en.wikipedia.org/wiki/Calmodulin-regulated_spectrin-associated_CKK_domain |
In molecular biology, the calponin family repeat is a 26 amino acid protein domain. Calponin 1 (CNN1) contains three copies of this domain. This domain is also found in vertebrate smooth muscle protein (SM22 or transgelin), and a number of other proteins whose physiological role is not yet established, including Drosophila synchronous flight muscle protein SM20, Caenorhabditis elegans unc-87 protein, rat neuronal protein NP25, and an Onchocerca volvulus antigen. == References == | https://en.wikipedia.org/wiki/Calponin_family_repeat |
In molecular biology, the calreticulin protein family is a family of calcium-binding proteins. This family includes Calreticulin, Calnexin and Camlegin. == References == | https://en.wikipedia.org/wiki/Calreticulin_protein_family |
In molecular biology, the calx-beta motif is a protein motif which is present as a tandem repeat in the cytoplasmic domains of Calx sodium-calcium exchangers, which are used to expel calcium from cells. This motif overlaps domains used for calcium binding and regulation. The calx-beta motif is also present in the cytoplasmic tail of mammalian integrin-beta4, which mediates the bi-directional transfer of signals across the plasma membrane, as well as in some cyanobacterial proteins. This motif contains a series of beta-strands and turns that form a self-contained beta-sheet. == References == | https://en.wikipedia.org/wiki/Calx-beta_motif |
In molecular biology, the carboxypeptidase A inhibitor family is a family of proteins which is represented by the well-characterised metallocarboxypeptidase A inhibitor (MCPI) from potatoes, which belongs to the MEROPS inhibitor family I37, clan IE. It inhibits metallopeptidases belonging to MEROPS peptidase family M14, carboxypeptidase A. In Russet Burbank potatoes, it is a mixture of approximately equal amounts of two polypeptide chains containing 38 or 39 amino acid residues. The chains differ in their amino terminal sequence only and are resistant to fragmentation by proteases. The structure of the complex between bovine carboxypeptidase A and the 39-amino-acid carboxypeptidase A inhibitor from potatoes has been determined at 2.5-Angstrom resolution.The potato inhibitor is synthesised as a precursor, having a 29 amino acid N-terminal signal peptide, a 27 amino acid pro-peptide, the 39 amino acid mature inhibitor region and a 7 amino acid C-terminal extension. The 7 amino acid C-terminal extension is involved in inhibitor inactivation and may be required for targeting to the vacuole where the mature active inhibitor accumulates.The N-terminal region and the mature inhibitor are weakly related to other solananaceous proteins found in this family, from potato, tomato and henbane, which have been incorrectly described as metallocarboxypeptidase inhibitors. | https://en.wikipedia.org/wiki/Carboxypeptidase_A_inhibitor |
In molecular biology, the catalase-related immune-responsive domain is a protein domain found in catalases. This domain carries the immune-responsive amphipathic octa-peptide that is recognised by T cells. == References == | https://en.wikipedia.org/wiki/Catalase-related_immune-responsive_domain |
In molecular biology, the cerato-platanin family of proteins includes the phytotoxin cerato-platanin (CP) produced by the Ascomycete Ceratocystis platani. CP homologs are also found in both the Ascomycota and the Basidiomycota branches of Dikarya. This toxin causes the severe plant disease: canker stain. This protein occurs in the cell wall of the fungus and is involved in the host-pathogen interaction and induces both cell necrosis and phytoalexin synthesis which is one of the first plant defense-related events. | https://en.wikipedia.org/wiki/Cerato-platanin |
CP, like other fungal surface proteins, is able to self-assemble in vitro. CP is a 120 amino acid protein, containing 40% hydrophobic residues. It is one of the rare examples of protein in which contains a Hopf link. | https://en.wikipedia.org/wiki/Cerato-platanin |
The link is formed by covalent loops - the pieces of protein backbone closed by two disulphide bonds (formed out of four cysteine residues). The N-terminal region of CP is very similar to cerato-ulmin, a phytotoxic protein produced by the Ophiostoma species belonging to the hydrophobin family, which also self-assembles. == References == | https://en.wikipedia.org/wiki/Cerato-platanin |
In molecular biology, the chitinase A N-terminal domain is found at the N-terminus of a number of bacterial chitinases and similar viral proteins. It is organised into a fibronectin III module domain-like fold, comprising only beta strands. Its function is not known, but it may be involved in interaction with the enzyme substrate, chitin. It is separated by a hinge region from the catalytic domain; this hinge region is probably mobile, allowing the N-terminal domain to have different relative positions in solution. == References == | https://en.wikipedia.org/wiki/Chitinase_A_N-terminal_domain |
In molecular biology, the chloramphenicol phosphotransferase-like protein family includes the chloramphenicol 3-O phosphotransferase (CPT) expressed by Streptomyces venezuelae. Chloramphenicol (Cm) is a metabolite produced by this bacterium that can inhibit ribosomal peptidyl transferase activity and therefore protein production. By transferring a phosphate group to the C-3 hydroxyl group of Cm, CPT inactivates this potentially lethal metabolite. == References == | https://en.wikipedia.org/wiki/Chloramphenicol_phosphotransferase-like_protein_family |
In molecular biology, the choline/ethanolamine kinase family includes choline kinase(EC 2.7.1.32) and ethanolamine kinase (EC 2.7.1.82). Ethanolamine and choline are major membrane phospholipids, in the form of glycerophosphoethanolamine and glycerophosphocholine. Ethanolamine is also a component of the glycosylphosphatidylinositol (GPI) anchor, which is necessary for cell-surface protein attachment. The de novo synthesis of these phospholipids begins with the creation of phosphoethanolamine and phosphocholine by ethanolamine and choline kinases in the first step of the CDP-ethanolamine pathway. | https://en.wikipedia.org/wiki/Choline/ethanolamine_kinase_family |
There are two putative choline/ethanolamine kinases (C/EKs) in the Trypanosoma brucei genome. Ethanolamine kinase has no choline kinase activity and its activity is inhibited by ADP. Inositol supplementation represses ethanolamine kinase, decreasing the incorporation of ethanolamine into the CDP-ethanolamine pathway and into phosphatidylethanolamine and phosphatidylcholine. == References == | https://en.wikipedia.org/wiki/Choline/ethanolamine_kinase_family |
In molecular biology, the chromo shadow domain is a protein domain which is distantly related to the chromodomain. It is always found in association with a chromodomain. Proteins containing a chromo shadow domain include Drosophila and human heterochromatin protein Su(var)205 (HP1); and mammalian modifier 1 and modifier 2. | https://en.wikipedia.org/wiki/Chromo_shadow_domain |
Chromo shadow domains self-aggregate, bringing together the nucleosomes to which their proteins are bound and thus condense the chromatin region they are associated with. Condensed chromatin is not able to be transcribed as the transcription factors and enzymes are not able to access to DNA sequence in this form. Hence chromoshadow domain containing proteins repress gene transcription. | https://en.wikipedia.org/wiki/Chromo_shadow_domain |
In molecular biology, the citrate synthase family of proteins includes the enzymes citrate synthase EC 2.3.3.1, and the related enzymes 2-methylcitrate synthase EC 2.3.3.5 and ATP citrate lyase EC 2.3.3.8. Citrate synthase is a member of a small family of enzymes that can directly form a carbon-carbon bond without the presence of metal ion cofactors. It catalyses the first reaction in the Krebs' cycle, namely the conversion of oxaloacetate and acetyl-coenzyme A into citrate and coenzyme A. This reaction is important for energy generation and for carbon assimilation. The reaction proceeds via a non-covalently bound citryl-coenzyme A intermediate in a 2-step process (aldol-Claisen condensation followed by the hydrolysis of citryl-CoA). | https://en.wikipedia.org/wiki/Citrate_synthase_family |
Citrate synthase enzymes are found in two distinct structural types: type I enzymes (found in eukaryotes, Gram-positive bacteria and archaea) form homodimers and have shorter sequences than type II enzymes, which are found in Gram-negative bacteria and are hexameric in structure. In both types, the monomer is composed of two domains: a large alpha-helical domain consisting of two structural repeats, where the second repeat is interrupted by a small alpha-helical domain. The cleft between these domains forms the active site, where both citrate and acetyl-coenzyme A bind. | https://en.wikipedia.org/wiki/Citrate_synthase_family |
The enzyme undergoes a conformational change upon binding of the oxaloacetate ligand, whereby the active site cleft closes over in order to form the acetyl-CoA binding site. The energy required for domain closure comes from the interaction of the enzyme with the substrate. Type II enzymes possess an extra N-terminal beta-sheet domain, and some type II enzymes are allosterically inhibited by NADH.2-methylcitrate synthase catalyses the conversion of oxaloacetate and propanoyl-CoA into (2R,3S)-2-hydroxybutane-1,2,3-tricarboxylate and coenzyme A. This enzyme is induced during bacterial growth on propionate, while type II hexameric citrate synthase is constitutive.ATP citrate lyase catalyses the Mg.ATP-dependent, CoA-dependent cleavage of citrate into oxaloacetate and acetyl-CoA, a key step in the reductive tricarboxylic acid pathway of CO2 assimilation used by a variety of autotrophic bacteria and archaea to fix carbon dioxide. | https://en.wikipedia.org/wiki/Citrate_synthase_family |
ATP citrate lyase is composed of two distinct subunits. In eukaryotes, ATP citrate lyase is a homotetramer of a single large polypeptide, and is used to produce cytosolic acetyl-CoA from mitochondrial produced citrate. == References == | https://en.wikipedia.org/wiki/Citrate_synthase_family |
In molecular biology, the cloacin immunity protein is produced by bacteria if they contain a certain plasmid. It inhibits the polypeptide bacterial toxin, cloacin, which is produced by the same or other bacteria. It complexes with cloacin in equimolar quantities and inhibits it by binding with high affinity to the cloacin C-terminal catalytic domain.The immunity protein is relatively small, containing 85 amino acids. | https://en.wikipedia.org/wiki/Cloacin_immunity_protein |
An extra ribosome binding site has been found to precede the immunity gene on the polycistronic Clo DF13 mRNA, which perhaps accounts for the fact that, in cloacinogenic cells, more immunity protein than cloacin is synthesised. Comparison of the complete amino acid sequence of the Clo DF13 immunity protein with that of the Col E3 and Col E6 immunity proteins reveals extensive similarities in primary structure, although Col E3 and Clo DF13 immunity proteins are exchangeable only to a low extent in vivo and in vitro. == References == | https://en.wikipedia.org/wiki/Cloacin_immunity_protein |
In molecular biology, the cohesin domain is a protein domain. It interacts with a complementary domain, termed the dockerin domain. The cohesin-dockerin interaction is the crucial interaction for complex formation in the cellulosome.The scaffolding component of the cellulolytic bacterium Clostridium thermocellum is a non-hydrolytic protein which organises the hydrolytic enzymes into a large complex, called the cellulosome. Scaffoldin comprises a series of functional domains, amongst which is a single cellulose-binding domain and nine cohesin domains which are responsible for integrating the individual enzymatic subunits into the complex. | https://en.wikipedia.org/wiki/Cohesin_domain |
In molecular biology, the cold-shock domain (CSD) is a protein domain of about 70 amino acids which has been found in prokaryotic and eukaryotic DNA-binding proteins. Part of this domain is highly similar to the RNP-1 RNA-binding motif.When Escherichia coli is exposed to a temperature drop from 37 to 10 degrees Celsius, a 4–5 hour lag phase occurs, after which growth is resumed at a reduced rate. During the lag phase, the expression of around 13 proteins, which contain cold shock domains is increased 2–10 fold. These so-called cold shock proteins induced in the cold shock response are thought to help the cell to survive in temperatures lower than optimum growth temperature, by contrast with heat shock proteins induced in the heat shock response, which help the cell to survive in temperatures greater than the optimum, possibly by condensation of the chromosome and organisation of the prokaryotic nucleoid. == References == | https://en.wikipedia.org/wiki/Cold-shock_domain |
In molecular biology, the collagen triple helix or type-2 helix is the main secondary structure of various types of fibrous collagen, including type I collagen. In 1954, Ramachandran & Kartha (13, 14) advanced a structure for the collagen triple helix on the basis of fiber diffraction data. It consists of a triple helix made of the repetitious amino acid sequence glycine-X-Y, where X and Y are frequently proline or hydroxyproline. Collagen folded into a triple helix is known as tropocollagen. Collagen triple helices are often bundled into fibrils which themselves form larger fibres, as in tendons. | https://en.wikipedia.org/wiki/Collagen_helix |
In molecular biology, the condensation domain is a protein domain found in many multi-domain enzymes which synthesise peptide antibiotics. This domain catalyses a condensation reaction to form peptide bonds in non-ribosomal peptide biosynthesis. It is usually found to the carboxy side of a phosphopantetheine binding domain (pp-binding). It has been shown that mutations in the HHXXXDG sequence motif in this domain abolish activity suggesting this is part of the active site. == References == | https://en.wikipedia.org/wiki/Condensation_domain |
In molecular biology, the copper type II ascorbate-dependent monooxygenases are a class of enzymes that require copper as a cofactor and which use ascorbate as an electron donor. This family contains two related enzymes, dopamine beta-monooxygenase EC 1.14.17.1 and peptidylglycine alpha-amidating monooxygenase EC 1.14.17.3. There are a few regions of sequence similarities between these two enzymes, two of these regions contain clusters of conserved histidine residues which are most probably involved in binding copper. | https://en.wikipedia.org/wiki/Copper_type_II_ascorbate-dependent_monooxygenase |
In molecular biology, the coronavirus frameshifting stimulation element is a conserved stem-loop of RNA found in coronaviruses that can promote ribosomal frameshifting. Such RNA molecules interact with a downstream region to form a pseudoknot structure; the region varies according to the virus but pseudoknot formation is known to stimulate frameshifting. In the classical situation, a sequence 32 nucleotides downstream of the stem is complementary to part of the loop. | https://en.wikipedia.org/wiki/Coronavirus_frameshifting_stimulation_element |
In other coronaviruses, however, another stem-loop structure around 150 nucleotides downstream can interact with members of this family to form kissing stem-loops and stimulate frameshifting.Other RNA families identified in the coronavirus include the coronavirus 3′ stem-loop II-like motif (s2m), the coronavirus packaging signal and the coronavirus 3′ UTR pseudoknot. During protein synthesis, rapidly changing conditions in the cell can cause ribosomal pausing. In coronaviruses, this can affect growth rate and trigger translational abandonment. This releases the ribosome from the mRNA and the incomplete polypeptide is targeted for destruction. | https://en.wikipedia.org/wiki/Coronavirus_frameshifting_stimulation_element |
In molecular biology, the crustacean neurohormone family of proteins is a family of neuropeptides expressed by arthropods. The family includes the following types of neurohormones: Crustacean hyperglycaemic hormone (CHH). CHH is primarily involved in blood sugar regulation, but also plays a role in the control of moulting and reproduction. Moult-inhibiting hormone (MIH). | https://en.wikipedia.org/wiki/Crustacean_neurohormone_family |
MIH inhibits Y-organs where moulting hormone (ecdysteroid) is secreted. A moulting cycle is initiated when MIH secretion diminishes or stops. Gonad-inhibiting hormone (GIH), also known as vitellogenesis-inhibiting hormone (VIH) because of its role in inhibiting vitellogenesis in female animals. | https://en.wikipedia.org/wiki/Crustacean_neurohormone_family |
Mandibular organ-inhibiting hormone (MOIH). MOIH represses the synthesis of methyl farnesoate, the precursor of insect juvenile hormone III in the mandibular organ. Ion transport peptide (ITP) from locust. | https://en.wikipedia.org/wiki/Crustacean_neurohormone_family |
ITP stimulates salt and water reabsorption and inhibits acid secretion in the ileum of the locust. Caenorhabditis elegans uncharacterised protein ZC168.2.These neurohormones are peptides of 70 to 80 amino acid residues which are processed from larger precursors. They contain six conserved cysteines that are involved in disulfide bonds. == References == | https://en.wikipedia.org/wiki/Crustacean_neurohormone_family |
In molecular biology, the cyanobacterial clock proteins are the main circadian regulator in cyanobacteria. The cyanobacterial clock proteins comprise three proteins: KaiA, KaiB and KaiC. The kaiABC complex may act as a promoter-nonspecific transcription regulator that represses transcription, possibly by acting on the state of chromosome compaction. This complex is expressed from a KaiABC operon. | https://en.wikipedia.org/wiki/Cyanobacterial_clock_proteins |
See also: bacterial circadian rhythms In the complex, KaiA enhances the phosphorylation status of kaiC. In contrast, the presence of kaiB in the complex decreases the phosphorylation status of kaiC, suggesting that kaiB acts by antagonising the interaction between kaiA and kaiC. The activity of KaiA activates kaiBC expression, while KaiC represses it. | https://en.wikipedia.org/wiki/Cyanobacterial_clock_proteins |
Also in the KaiC family is RadA/Sms, a highly conserved eubacterial protein that shares sequence similarity with both RecA strand transferase and lon protease. The RadA/Sms family are probable ATP-dependent proteases involved in both DNA repair and degradation of proteins, peptides, glycopeptides. They are classified in as non-peptidase homologues and unassigned peptidases in MEROPS peptidase family S16 (lon protease family, clan SJ). RadA/Sms is involved in recombination and recombinational repair, most likely involving the stabilisation or processing of branched DNA molecules or blocked replication forks because of its genetic redundancy with RecG and RuvABC. | https://en.wikipedia.org/wiki/Cyanobacterial_clock_proteins |
In molecular biology, the cyclase-associated protein family (CAP) is a family of highly conserved actin-binding proteins present in a wide range of organisms including yeast, flies, plants, and mammals. CAPs are multifunctional proteins that contain several structural domains. CAP is involved in species-specific signalling pathways. In Drosophila, CAP functions in Hedgehog-mediated eye development and in establishing oocyte polarity. | https://en.wikipedia.org/wiki/Cyclase-associated_protein_family |
In Dictyostelium discoideum (social amoeba), CAP is involved in microfilament reorganisation near the plasma membrane in a PIP2-regulated manner and is required to perpetuate the cAMP relay signal to organise fruitbody formation. In plants, CAP is involved in plant signalling pathways required for co-ordinated organ expansion. In yeast, CAP is involved in adenylate cyclase activation, as well as in vesicle trafficking and endocytosis. In both yeast and mammals, CAPs appear to be involved in recycling G-actin monomers from ADF/cofilins for subsequent rounds of filament assembly. In mammals, there are two different CAPs (CAP1 and CAP2) that share 64% amino acid identity. | https://en.wikipedia.org/wiki/Cyclase-associated_protein_family |
In molecular biology, the cyclin-dependent kinase regulatory subunit family is a family of proteins consisting of the regulatory subunits of cyclin-dependent protein kinases. In eukaryotes, cyclin-dependent protein kinases interact with cyclins to regulate cell cycle progression, and are required for the G1 and G2 stages of cell division. The proteins bind to a regulatory subunit, cyclin-dependent kinase regulatory subunit (CKS), which is essential for their function. This regulatory subunit is a small protein of 79 to 150 residues. | https://en.wikipedia.org/wiki/Cyclin-dependent_kinase_regulatory_subunit_family |
In yeast (gene CKS1) and in fission yeast (gene suc1) a single isoform is known, while mammals have two highly related isoforms. The regulatory subunits exist as hexamers, formed by the symmetrical assembly of 3 interlocked homodimers, creating an unusual 12-stranded beta-barrel structure. Through the barrel centre runs a 12A diameter tunnel, lined by 6 exposed helix pairs. Six kinase units can be modelled to bind the hexameric structure, which may thus act as a hub for cyclin-dependent protein kinase multimerisation.This family includes the CKS1B and CKS2 genes in mammals. | https://en.wikipedia.org/wiki/Cyclin-dependent_kinase_regulatory_subunit_family |
In molecular biology, the cytochrome c assembly protein family includes various proteins involved in cytochrome c assembly from mitochondria and bacteria. Members of this family include: CycK from Rhizobium leguminosarum, CcmC from Escherichia coli and Paracoccus denitrificans, and orf240 from Triticum aestivum (Wheat) mitochondria. The members of this family are probably integral membrane proteins with six predicted transmembrane helices that may comprise the membrane component of an ABC (ATP binding cassette) transporter complex. This transporter may be necessary for transport of some component needed for cytochrome c assembly. | https://en.wikipedia.org/wiki/Cytochrome_c_assembly_protein_family |
One member, R. leguminosarum CycK, contains a putative haem-binding motif. Wheat orf240 also contains a putative haem-binding motif and is a proposed ABC transporter with c-type haem as its proposed substrate. However it seems unlikely that all members of this family transport haem or c-type apocytochromes because P. denitrificans CcmC transports neither. == References == | https://en.wikipedia.org/wiki/Cytochrome_c_assembly_protein_family |
In molecular biology, the cytotoxic necrotising factor family of proteins includes bacterial cytotoxic necrotising factor proteins and the related dermonecrotic toxin (DNT) from Bordetella species. Cytotoxic necrotizing factor 1 (CNF1) is a toxin whose structure from Escherichia coli revealed a 4-layer alpha/beta/beta/alpha structure containing mixed beta-sheets. CNF1 is expressed in strains of E. coli causing uropathogenic and neonatal meningitis. CNF1 alters host cell actin cytoskeleton and promotes bacterial invasion of the blood–brain barrier endothelial cells. | https://en.wikipedia.org/wiki/Cytotoxic_necrotising_factor_family |
CNF1 belongs to a unique group of large cytotoxins that cause constitutive activation of Rho guanosine triphosphatases (GTPases), which are key regulators of the actin cytoskeleton . Bordetella dermonecrotic toxin (DNT) stimulates the assembly of actin stress fibres and focal adhesions by deamidating or polyaminating Gln63 of the small GTPase Rho. DNT is an A-B toxin composed of an N-terminal receptor-binding (B) domain and a C-terminal enzymatically active (A) domain. == References == | https://en.wikipedia.org/wiki/Cytotoxic_necrotising_factor_family |
In molecular biology, the di-haem cytochrome c peroxidase family is a group of distinct cytochrome c peroxidases (CCPs) that contain two haem groups. Similar to other cytochrome c peroxidases, they reduce hydrogen peroxide to water using c-type haem as an oxidizable substrate. However, since they possess two, instead of one, haem prosthetic groups, this family of bacterial CCPs reduce hydrogen peroxide without the need to generate semi-stable free radicals. The two haem groups have significantly different redox potentials. | https://en.wikipedia.org/wiki/Di-haem_cytochrome_c_peroxidase |
The high potential (+320 mV) haem feeds electrons from electron shuttle proteins to the low potential (-330 mV) haem, where peroxide is reduced (indeed, the low potential site is known as the peroxidatic site). The CCP protein itself is structured into two domains, each containing one c-type haem group, with a calcium-binding site at the domain interface. This family also includes MauG proteins, whose similarity to di-haem CCP was previously recognised. == References == | https://en.wikipedia.org/wiki/Di-haem_cytochrome_c_peroxidase |
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