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GrpE , co-chaperone of E.coli, participates actively in the response to hyperosomotic and heat shock by preventing the aggregation of stress-denatured proteins in association with DnaK. This protein is the nucleotide exchange factor for DnaK and may function as a thermosensor. Several rounds of ATP-dependent interactions between DnaJ, DnaK and GrpE are required for fully efficient folding.

6-PyruvoylTetrahydropterin Synthase is part of the family of lyases, specifically those carbon-oxygen lyases acting on phosphates. 6-PyruvoylTetrahydropterin Synthase catalyzes the elimination of inorganic triphosphate from dihydroneopterin triphosphate, which is the second and irreversible step in the biosynthesis of tetrahydrobiopterin from GTP. Tetrahydrobiopterin, is a necessary cofactor and regulator of a range of enzyme activities, including enzymes involved in serotonin biosynthesis and NO synthase activity. Mutations in 6-PyruvoylTetrahydropterin Synthase gene result in hyperphenylalaninemia.

VPS28 is a subunit of the ESCRT-I complex (endosomal complexes required for transport) involved in the sorting of ubiquitinated proteins. VPS28 is involved in endosomal sorting of cell surface receptors using a multivesicular body/late endosome pathway. VSP28 binding with the TSG101 may have significant roles in budding of Retroviruses, such as HIV-1 and Ebola virus.
VSP28 interacts with TSG101, VPS37B, VPS37C, FAM125A and FAM125B, and also with VPS36, this interaction mediates the association with the ESCRT-II complex. Furthermore it interacts with SNF8 and VPS25 and CEP55.

Recoverin is a member of the recoverin family of neuronal calcium sensors. Recoverin is a heterogeneously acylated calcium-binding and intracellular signal transduction 23kDa protein in the photoreceptor cells of retina. Recoverin contains four EF-hands, of which two bind Ca. Ca-induced extrusion of the acyl group from a hydrophobic cleft in the protein drives the translocation of recoverin from solution to the disc membrane. Recoverin may prolong the termination of the phototransduction cascade in the retina by blocking the phosphorylation of photo-activated rhodopsin. Recoverin plays a key role in the inhibition of rhodopsin kinase, a molecule that regulates the phosphorylation of rhodopsin. This in due course controls the ability of the eye to adapt to, and recover from, exposure to the presence of light. Recoverin is a detectable serologic protein that is expressed in patients with cancer-associated retinopathy, a paraneoplastic syndrome.

The epidermal growth factor receptor (EGF R) subfamily of receptor tyrosine kinases comprises four members: EGF R (also known as HER1, ErbB1 or ErbB), ErbB2 (Neu, HER-2), ErbB3 (HER-3), and ErbB4 (HER-4). All family members are type I transmembrane glycoprotein that has an extracellular domain which contains two cysteine-rich domains separated by a spacer region that is involved in ligand-binding, and a cytoplasmic domain which has a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGF R gene encodes a 1210 amino acid (aa) residue precursor with a 24 aa putative signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGF R has been shown to bind a subset of the EGF family ligands, including EGF, amphiregulin, TGF-a , betacellulin, epiregulin, HBEGF and neuregulin-2 in the absence of a co-receptor. Ligand binding induces EGF R homodimerization as well as heterdimerization with ErbB2, resulting in kinase activation, tyrosine phosphorylation and cell signaling. EGF R can also be recruited to form heterodimers with the ligand-activated ErbB3 or ErbB4. EGF R signaling has been shown to regulate multiple biological functions including cell proliferation, differentiation, motility and apoptosis. In addition, EGF R signaling has also been shown to play a role in carcinogenesis.

Eledoisin is an undecapeptide formed in the venom gland of several species of octopuses and is used as a vasodilator and a contraction agent of extravascular smooth muscle.

Signal-Regulatory Protein Alpha, SIRPA belongs to the signal-regulatory-protein (SIRP) family, as well as the immunoglobulin super family. The members of the SIRP family are receptor-type transmembrane glycoproteins which are involved in the negative regulation of receptor tyrosine kinase-coupled signaling processes.
SIRPA can be phosphorylated by tyrosine kinases. The phospho-tyrosine residues of this PTP have been shown to recruit SH2 domain containing tyrosine phosphatases (PTP), and perform as substrates of PTPs. SIRPA take part in signal transduction mediated by a variety of growth factor receptors. CD47 has been shown to be a ligand for SIRPA.

Insulin-like Growth Factor-Binding Protein 7 (IGFBP7) is a member of the IGFBP family. IGFBP family members are all cysteine rich proteins with conserved cysteine and have an IGFBP domain, a Kazal-like domain and an Ig-like C2-type domain. IGFBP7 is expressed in a broad range of normal human tissues and it mostly shows reduced expression in cancer cell lines of prostate, breast, colon, and lung origin. IGFBP7 has a role in skeletal myogenesis by binding to IGF in a manner which inhibits IGF induced differentiation of skeletal myoblasts, without disturbing IGF induced proliferation. Moreover, IGFBP7 suppresses growth and colony formation of prostate and breast cancer cell lines via an IGF independent mechanism, which triggers a delay in the G1 phase of the cell cycle, and increased apoptosis.

INHBC, the beta C chain of inhibin, belongs to the TGF-beta superfamily. INHBC formulates heterodimers with beta A and beta B subunits. Other members of the TGF-beta superfamily are Actv's and Inhibins, hormones with contradictory roles which take part in pituitary, hypothalamic, and gonadal hormone secretion, as well as differentiation and growth of numerous cell types.

Gltathione S-transferase PI 2, also known as GSTP2 is multifunctional enzyme which is involved in theprotection of cellular components against anti-cancer drugs or peroxidative stress. Furthermore, down regulation of GSTP2induces an increase of oxidative damage in the pyramidal cells of the CA1&CA3 regions as well as in the granular layer ofthe dentate gyrus, which at the end leads to structural and functional damage.

STYX is a member of the protein-tyrosine phosphatase family. STYX has a Gly residue instead of a conserved Cys residue in the dsPTPase catalytic loop which renders it catalytically inactive as a phosphatase. Nevertheless, the binding pocket is adequately preserved to bind phosphorylated substrates, and possibly protect them from phosphatases. STYX takes part in spermiogenesis.

SUMF1 is a part of the SUMF protein family. SUMF1 catalyzes the hydrolysis of sulfate esters by oxidizing a cysteine residue in the substrate sulfatase to an active site 3-oxoalanine residue called C-alpha-formylglycine. Mutations in this gene will cause multiple sulfatase deficiency meaning a lysosomal storage disorder.

HSP27 or Estrogen-Regulated 24K proteinis a part of the mammalian small heat shock protein family. The protein is expressed constitutively in many tissues and its expression is increased to high levels after different types of stress including high temperatures, toxic metals, drugs and oxidants. Furthermore, Hsp27 is phosphorylated in vivo on three phosphorylation sites (Ser15, Ser78 and Ser82) by protein kinases including MAPKAP kinase 2 and the stress-activated protein kinase SAPK2 (p38).

Factor B is a protein, build from a single chain that circulates in the blood. Complement factor D cleaves and activates factor B, thus creating a catalytic subunit Bb and noncatalytic chain Ba. Subunit Bb is a serine protease that can bind to C3b and forms alternative pathway C3 convertase. Subunit Ba acts as an inhibitor for proliferation of lymphocytes, when Bb is part of the lymphocytes’ proliferation. The gene that codes for this protein is located on chromosome six.

MECP2 is the key modificator of eukaryotic genomes and has a crucial part in mammalian development.
Human proteins MECP2, MBD1, MBD2, MBD3, and MBD4 form a family of nuclear proteins linked by the existence in each of a methyl-CpG binding domain (MBD). Each one of these proteins, with the exception of MBD3, can bind specifically to methylated DNA. In addition, MECP2, MBD1 and MBD2 can inhibit transcription from methylated gene promoters. Unlike other MBD family members, MECP2 is X-linked and subject to X inactivation. MECP2 is expendable in stem cells, but is vital for embryonic development. MECP2 gene mutations are the cause of most cases of Rett syndrome, a progressive neurologic developmental disorder and one of the most common reasons of mental retardation in females.

Alpha crystallins are composed of two gene products ; alpha-A and alpha-B, for acidic and basic, respectively. Alpha crystallins can be induced by heat shock and are members of the small heat shock protein (sHSP also known as the HSP20). They act as molecular chaperones and hold them in in large soluble aggregates. These heterogeneous aggregates consist of 30-40 subunits; the alpha-A and alpha-B subunits have a 3:1 ratio, respectively. Two additional function of a-crystallins are an autokinase activity and participation in the intracellular architecture. Alpha-B is expressed widely in many tissues and organs and occurs in many neurological diseases.

GDF8 is a member of the bone morphogenetic protein (BMP) family and the TGF-beta superfamily. This group of proteins is characterized by a polybasic proteolytic processing site which is cleaved to produce a mature protein containing seven conserved cysteine residues. The members of this family are regulators of cell growth and differentiation in both embryonic and adult tissues. This gene is thought to encode a secreted protein which negatively regulates skeletal muscle growth.

Pramlintide acetate is a hormone that is released into the bloodstream, in a similar pattern as insulin. Pramlintide aids in the absorption of glucose by slowing gastric emptying, promoting satiety, and inhibiting inappropriate secretion of glucagon, a catabolic hormone that opposes the effects of insulin.

DERP1 is a thiol protease, with a preference for substrates with a large hydrophobic side chain in the P2 position, or with basic residues. DERP1 is a C1 peptidase family member. DERP1 has extensive endopeptidase specificity. DERP1 is N-glycosylated. N-glycanase treatment does not completely remove carbohydrates, suggesting that the protein contains additional glycosylation sites. DERP1 causes an allergic reaction in humans. Common symptoms of mite allergy are bronchial asthma, allergic rhinitis and conjunctivitis. DERP1 binds to IgE in 80% of patients with house dust allergy.

Plasmodium falciparum heat shock proteins (PfHSPs) contribute to immunopathological alterations in infected hosts PfHSP70s may have a significant function during parasite adaptation in its environments. They have also been a focus of considerable attention due to their immunodominant antigenic nature and their properties as mediators of protective immunity.

Angiopoietin-related protein 7 (ANGPTL7), belongs to the angiopoietin-like family of molecules. ANGPTL7 is expressed in the corneal stroma, trabecular meshwork, and sclera. ANGPTL7 production is up-regulated in trabecular meshwork cells by glucocorticoids and TGF-Beta and in cartilage by TNF-alpha.

Adiponectin, also referred to as Acrp30, AdipoQ and GBP-28, is a recently discovered 244 amino acid protein, the product of the apM1 gene, which is physiologically active and specifically and highly expressed in adipose cells (Adipokine). The protein belongs to the soluble defense collagen super family; it has a collagen-like domain structurally homologous with collagen VIII and X and complement factor C1q-like globular domain. APM-1 forms homotrimers, which are the building blocks for higher order complexes found circulating in serum.