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SGTA is a ubiquitously expressed protein that contains three TPR protein-protein interaction duplicates. SGTA takes part as a component of the androgen receptor (AR)-chaperone-cochaperone complex, functions as a cochaperone and participates in androgen signaling. SGTA binds directly to HSC70 and HSP70 and mediates their ATPase activity. SGTA gene encodes a protein that is able to interact with the chief nonstructural protein of parvovirus H-1 and 70-kDa heat shock cognate. In addition, SGTA interacts with Vpu and Gag from HIV-1, SARS-CoV accessory protein 7a, DNAJC5 and DNAJC5B. Since this transcript is expressed universally in several tissues, SGTA serves a housekeeping function. While being involved in apoptosis and androgen signaling, SGTA is a possible molecule for polycystic ovary syndrome, a disorder characterized by androgen excess, obesity and menstrual disturbances.

Clusterin also named Apolipoprotein J (APO-J) is a 75-80 kD disulfide-linked heterodimeric protein containing about 30% of N-linked carbohydrate rich in sialic acid but truncated forms targeted to the nucleus have also been identified.
The precursor polypeptide chain is cleaved proteolytically to remove the 22-mer secretory signal peptide and subsequently between residues 227/228 to generate the a and b chains. These are assembled in anti-parallel to give a heterodimeric molecule in which the cysteine-rich centers are linked by five disulfide bridges and are flanked by two predicted coiled-coil a-helices and three predicted amphipathic a-helices.
Across a broad range of species clusterin shows a high degree of sequence homology ranging from 70% to 80%. It is nearly ubiquitously expressed in most mammalian tissues and can be found in plasma, milk, urine, cerebrospinal fluid and semen.
It is able to bind and form complexes with numerous partners such as immunoglobulins, lipids, heparin, bacteria, complement components, paraoxonase, beta amyloid, leptin and others. Clusterin has been ascribed a plethora of functions such as phagocyte recruitment, aggregation induction, complement attack prevention, apoptosis inhibition, membrane remodeling, lipid transport, hormone transport and/or scavenging, matrix metalloproteinase inhibition.
A genuine function of clusterin has not been defined. One tempting hypothesis says that clusterin is an extracellular chaperone protecting cells from stress induced insults caused by degraded and misfolded protein precipitates.
Clusterin is up- or down regulated on the mRNA or protein level in many pathological and clinically relevant situations including cancer, organ regeneration, infection, Alzheimer disease, retinitis pigmentosa, myocardial infarction, renal tubular damage, autoimmunity and others.

CKMT1A is in charge of the transfer of high energy phosphate from mitochondria to the cytosolic carrier, creatine. CKMT1A is a member of the creatine kinase isoenzyme family and exists as two isoenzymes, sarcomeric MtCK and ubiquitous MtCK, encoded by separate genes. Mitochondrial creatine kinase arises in two different oligomeric forms: dimers and octamers, unlike the exclusively dimeric cytosolic creatine kinase isoenzymes. Numerous malignant cancers with poor prognosis have displayed overexpression of ubiquitous mitochondrial creatine kinase which is linked to high energy turnover and inability to remove cancer cells through apoptosis.

Nectin-1, also referred to as ED4, is a poliovirus receptor- related 1 protein is a part of the Nectin family. Nectin-1 endorses cell-cell contacts by forming homophilic or heterophilic trans-dimers. Heterophilic interactions among PVRL1/nectin-1 & PVRL4/nectin-4 and among PVRL1/nectin-1 & PVRL3/nectin-3 have been found. Nectin-1 acts as an entry receptor for herpes simplex virus & pseudorabies virus as well. Likewise, Neurite outgrowth-promoting activity has been shown by Nectin-1.

AMRC10 is a protein which contains an armadillo repeat and transmembrane domain. Upregulation of the AMRC10 gene has a role in hepatocellular carcinoma. AMRC10 decreases the transcriptional activity of the tumor suppressor protein p53 through direct interaction with the DNA-binding domain of p53, moreover it might play a role in cell growth and survival.

Oral cancer-overexpressed protein 1 (ORAOV1) is a candidate oncogene in the 11q13 chromosomal region. Functional analyses showed that ORAOV1 was involved in the regulation of HeLa cell growth via its effect on cell cycle and apoptosis. ORAOV1 is widely expressed; it has a high expression in the placenta, kidney and skeletal muscle. ORAOV1 is amplified and overexpressed in oral cancer cells.

Jumonji Domain Containing 6, also known as JMJD6 performs as a lysyl-hydroxylase which catalyzes 5-hydroxylation on specific lysine residues of target proteins for instance U2AF2/U2AF65 and LUC7L2, as a regulator of RNA splicing by mediating 5-hydroxylation of U2AF2/U2AF65, affecting the pre-mRNA splicing activity of U2AF2/U2AF65. Additionally to peptidyl-lysine 5-dioxygenase activity, JMJD6 performs as an RNA hydroxylase, as proposed by its ability to bind single strand RNA. Furthermore, it acts as an arginine demethylase which demethylates histone H3 at 'Arg-2' (H3R2me) as well as histone H4 at 'Arg-3' (H4R3me), thus taking a part in histone code.

CDHR5, also referred to ascadherin-related family member 5, is a calcium-dependent cell adhesion protein. CDHR5 is located in coated pits, and is expressed during lung and kidney developmentat at the lateral and basal surfaces of epithelia.

Ro 60 kDa autoantigen is an RNA-binding protein that binds to several small cytoplasmic RNA molecules known as Y RNAs. SSA2 may stabilize these RNAs from degradation. Sera taken from patients with Systemic Lupus Erythematosus (SLE) often contains antibodies that react with the normal cellular SSA2 protein as if this antigen was foreign.

Cell Growth Regulator with EF-Hand Domain 1, also known as CGREF1 is a secreted calcium ion binding protein. CGREF1 includes two EF-hand domains & both EF-hands are essential for function. CGREF1 is most likely digested extracellularly by an unfamiliar serine protease generating extremely hydrophobic bioactive peptides. CGREF1 mediates cell-cell adhesion in a calcium-dependent manner. In addition, CGREF1 is capable to inhibit growth in more than a few cell lines.

Glypican 4, also known as GPC4, is part of a family of glycosylphosphatidylinositol (GPI)-anchored heparan sulphate proteoglycans (HSPGs) which take part in the control of cell division and growth regulation. GPC4 is broadly expressed in human tissues, including lung, kidney, heart, placenta, skeletal muscle, and pancreas. In addition, GPC4 has been shown to be present in astrocytes, haematopoietic-progenitor and bone-marrow-stromal cells.

Glutathione reductase (GSR) belongs to the class-I pyridine nucleotide-disulfide oxidoreductase family. The GSR enzyme is a homodimeric flavoprotein and has a role in maintaining glutathione (GSH) in its reduced form by catalyzing the reduction of glutathione disulfide (GSSG): GSSG + NADPH + H+ ->2GSH + NADP+. In the majority of eukaryotic cells, GSR upholds the ratio of [GSH] / [GSSG], and partakes in quite a few critical functions such as the detoxification of reactive oxygen species as well as protein and DNA biosynthesis.

Cytochrome b-c1 complex subunit 2, mitochondrial (UQCRC2) is a member of the peptidase M16 family. UQCRC2 is a component of the ubiquinol-cytochrome c reductase complex (complex III), which is a part of the mitochondrial respiratory chain. UQCRC2 is essential for the compilation of the complex.

MAGE belongs to the MAGE gene family, that comprises 12 known genes, of which 6 are expressed in tumors. The Melanoma-associated antigen 3 genes were originally isolated from different kinds of tumors, and based on their virtually limited tumor-specific expression in adult tissues, they were used as targets for cancer immunotherapy. MAGEA3 is a tumor-specific antigen extensively expressed in solid and hematologic malignancies, but not in normal tissues, with the exclusion of testis and placenta. Consequently, MAGEA3 is an outstanding candidate tumor antigen.

Histidyl-tRNA synthetase (HARS) functions to catalyze the aminoacylation of tRNAs by their corresponding amino acids. HARS is a member of the class II family of aminoacyl-tRNA synthetases. HARS is responsible for the synthesis of histidyl-transfer RNA, which is vital for the incorporation of histidine into proteins. HARS is a frequent target of autoantibodies in the human autoimmune disease polymyositis/dermatomyositis.

Cytokeratin 23 (KRT23) is a 422 amino acid intermediate filament protein. The human KRT23 gene is found on chromosome 17q21.2. Type I cytokeratins consist of acidic proteins which are organized in pairs of heterotypic keratin chains. The cytokeratin proteins have an essential role in differentiation, plus tissue specialization and function, and epithelial cells structure maintenance. Cytokeratins are portrayed to be differentiation markers in a number of epithelial cancers.

Cardiotrophin 1 (CT-1) is a 201 amino acid member of the interleukin-6 superfamily. It was identified by its ability to induce hypertrophic response in cardiac myocytes. CT-1 mRNA levels were found both in cardiac myocytes and in cardiac nonmyocytes. CT 1 was also detected in abundance in normal adult human lung and was expressed in both fetal and adult airway smooth muscle cells. CT 1 activates gp130 dependent signaling and stimulates the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway to transduce hypertrophic and cytoprotective signals in cardiac myocytes.
CT 1 has also a neurotrophic function. CTF1 deficiency causes increased motoneuron cell death in spinal cord and brainstem nuclei of mice during a period between embryonic day 14 and the first postnatal week. Moreover, CT-1 is a hepatocyte survival factor that efficiently reduces hepatocellular damage in animal models of acute liver injury. Cardiotrophin 1 expression is augmented after hypoxic stimulation and it can protect cardiac cells when added either prior to simulated ischaemia or at the time of reoxygenation following simulated ischaemia. Cardiotrophin 1 can induce expression of the protective heat shock proteins (hsps) in cardiac cells.
Cardiotrophin-1 increased ventricular expression of ANP, brain natriuretic peptide (BNP) and angiotensinogen mRNA.
Cardiophin 1 levels were significantly elevated in patients with heart failure, patients with dilatative cardiomyopathy, moderate/severe mitral regurgitation, stable and unstable angina and after acute myocardial infarction.

Adiponectin is an adipocyte specific secreted protein that circulates in the plasma. It is induced during adipocyte differentiation and its secretion is stimulated by insulin. Mouse adiponectin shares about 83% amino acid identity with that human. Adiponectin plays a role in various physiological processes such as energy homeostasis and obesity. Adiponectin is reduced in obese humans, and decreased level is associated with insulin resistance and hyperinsulinemia.

Connective Tissue Growth Factor belongs to the CCN family of proteins. The CCN family presently consists of six members in human also known as: Cyr61 (Cystein rich 61), CTGF (Connective Tissue Growth Factor), Nov (Nephroblastoma Overexpressed gene), WISP-1, 2 and 3 (Wnt-1 Induced Secreted Proteins). The CCN genes encode secreted proteins associated with the Extracellular Matrix (ECM) and cell membrane.
CCN proteins are matricellular proteins which are involved in the regulation of various cellular functions including: proliferation, differentiation, survival, adhesion and migration. They are expressed in derivatives of the three embryonic sheets and are implicated in the development of kidney, nervous system, muscle, bone marrow, cartilage and bone. During adulthood, they are implicated in wound healing, bone fracture repair, and pathologies such as: fibrosis, vascular ailments and tumorigenesis.
Full length secreted CCN proteins can show an antiproliferative activity, whereas truncated isoforms are likely to stimulate proliferation and behave as oncogenes.
The full length protein consists of four modulesModule I shares partial identity with the N-terminal part of the IGFBPs.
Module II includes a stretch of 70amino acid residues – which shares sequence identity with the Von Willebrand Factor Type C repeat (VWC).
Module III contains sequences sharing identity with the Thrombospondin type 1 repeat (TSP1) (WSXCSXXCG), which is thought to be implicated in the binding of sulfated glycoconjugates and to be important for cell adhesion.
Module IV, also designated CT, is encoded by exon5. It is the leasts conserved one of the four domains at the level of nucleotide sequence, but it appears to be critical for several of the biological functions attributed to the CCN proteins. Module IV resembles the CT domain of several extracellular protein including, Von Willebrand's factor and mucins. Sequence similarities to binding motifs are also found within this domain.
Proteolysis of the secreted full-length CCN proteins that has been reported in the case of CCN2 and CCN3 might result in the production of CCN-derived peptides with high affinity for ligands that full-length CNN proteins bind only poorly. Amino-truncated CCN2 isoforms were biologically active whereas no specific biological activity has been attributed to the truncated CCN3. Although the molecular processes underlying the production of these secreted isoforms is presently unknown, it is important to note that proteolysis occur at the same amino acid residues in both CCN2 and CCN3. An elevated expression of CCN2 has also been detected by Northern blotting in human invasive mammary ductal carcinomas, dermatofibromas, pyogenic granuloma, endothelial cells of angiolipomas and angioleiomyomas, and in pancreatic tumors. A study performed with chondrosarcomas representative of various histological grades established that CCN2 expression was closely correlated with increasing levels of malignancy.
In agreement with CCN2 playing a role in brain tumor angiogenesis, immunocytochemistry studies indicated that both glioblastoma tumor cells and proliferating endothelial cells stained positive for CCN2. In astrocytomas, CCN2 expression was particularly elevated in high grade tumors, with a marked effect of CCN2 on cell proliferation. Downregulation of CCN2 expression in these cells was associated with a growth arrest at the G1/S transition while over-expression of CCN2 induced a two-fold increase of the number of cells in the G1 phase. Gene profiling analysis allowed to identify a set of about 50 genes whose expression might account for the proliferative activity of CCN2 in these cells.
CCN2 was seen in a higher proportion of mononuclear cells of patients with acute lymphoblastic leukemia.

Mouse CXCL16 is a nonELR motif including CXC chemokine with a transmembrane domain. Mouse CXCL16 cDNA encodes a 246 a.a. precursor protein with a putative 26 a.a. residue signal peptide, an 88 a.a. residue chemokine domain, an 87 a.a. residue mucinlike spacer region, a 22 a.a. residue transmembrane domain, and a 23 a.a. residue cytoplasmic tail.
CXCL16 induces a strong chemotactic response and calcium mobilization. Furthermore, CXCL16 acts as a scavenger receptor on macrophages, which specifically binds to OxLDL (oxidized low density lipoprotein), suggesting that it may be involved in pathophysiology such as atherogenesis.
Mouse CXCL16 is generated by dendritic cells in lymphoid organ T cell zones as well as by cells in the splenic red pulp both as membranebound and soluble forms. CXCR6/Bonzo (STRL33 and TYMSTR) is the receptor for CXCL16. CXCL16 is expressed in the spleen, lymph nodes, and Peyer patches. It is also expressed in non-lymphoid tissues such as lung, kidney, small intestine, and thymus, with weak expression in heart and liver and no expression in brain and purified B- and T-cells.
CXCL16 deficiency is linked to breast cancer progression. In addition, CXCL16 is involved in immunological liver injury by regulating T lymphocyte infiltration in liver tissue. Furtheremore, CXCL16 has a distinctive role in the maintenance of cardiac allograft tolerance mediated by natural killer T cells. Moreover, CXCL16 has a significant role in not only the production of IFN-gamma by NKT cells, but also promotion of Th1-inclined immune responses mediated by NKT cells.

MYCBP is a member of the AMY1 family. MYCBP (c-Myc binding protein) binds to the transactivation domain of c-Myc and stimulates the activation of E-box-dependent transcription. MYCBP translocates from the cytoplasm to the nucleus during S phase when increased expression of c-Myc occurs. MYCBP also associates with AKAP 149 and AKAP 84 in mitochondria of somatic cells and sperm, suggesting a role for MYCBP in spermatogenesis. MYCBP is highly expressed in the heart, placenta, pancreas, skeletal muscle and kidney. It is also present at low levels in the lung.

A natural cytotoxicity receptor (NCR) NKp46 has been shown to represent a novel NK cell-specific molecule involved in human NK cell activation. The natural cytotoxicity receptors (NCRs) are a recently characterized family of Ig-like activation receptors that appear to be major triggering receptors in tumor cell recognition. The three known NCRs include NKp46 and NKp30, which are expressed on circulating NKcells, and NKp44, which is expressed only on activating NK cells. NKp46 has been implicated in NK cell-mediated lysis of several autologous tumor cells, pathogen-infected cell lines and mononuclear phagocytes infected with an intracellular bacterium. The Lysis of tumor cells by NK-cells involves recognition by NKp46 of heparan sulfate moieties of membrane heparan sulfate proteoglycans. Furthermore, NKp46 is a surface receptor involved in NK-cell cell death by apoptosis. NKp46 has two extracellular Ig-like domains followed by a ~40 residue stalk region, a type I transmembrane domain, and a short cytoplasmic tail. The extracellular Ig-like domain of NKp46 (22-255aa) is purified by FPLC gel-filtration chromatography, after refolding of the isolated inclusion bodies in a redox buffer. In addition, engagement of the antigen with the monoclonal antibody stimulates intracellular calcium levels and the synthesis of cytokines. CD59 is an NKp46 coreceptor (by physical association) together they activate cytotoxicity of human NK-cells, their engagement results in tyrosine phosphorylation of CD3-zeta chains associated with NKp46. Reduced cell surface expression of NKp46 and other NK-cell receptors is linked to the impaired NK-cell cytolytic function in viremic HIV-1 infection.

O-Sialoglycoprotein Endopeptidase, also known as OSGEP is a member of the KAE1 / TsaD family. OSGEP is essential for the formation of threonylcarbamoyl group on adenosine at position 37 (t6A37) in tRNAs which read codons beginning with adenine. OSGEP take a direct catalytic part in the above reaction, however other proteins of the complex are required to fulfill this activity.

TBCA is a tubulin-folding protein which is involved in the early step of the tubulin folding pathway. TBCA is one of four proteins (cofactors A, D, E, and C) implicated in the pathway directing to properly folded beta-tubulin from folding intermediates. Cofactors A and D are thought to be a factor in capturing and stabilizing beta-tubulin in a quasi-native confirmation. TBCA is crucial for cell viability, if reduced it causes a decrease in the amount of soluble tubulin, alterations in microtubules and G1 cell cycle arrest. Cofactor E attaches to the cofactor D-tubulin complex, afterward, interaction with cofactor C triggers the release of tubulin polypeptides that are committed to the native state.