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Pyrroline-5-carboxylate reductase 2 isoform 1 (PYCR2) is a member of the pyrroline-5-carboxylate reductase family. PYCR2 protein catalyzes the conversion of pyrroline-5-carboxylate to proline, which is the last step in proline biosynthesis. The three substrates of the PYCR2 enzyme are L-proline, NAD+, and NADP+, while its four products are 1-pyrroline-5-carboxylate, NADH, NADPH, and H+.

Troponin I (TnI), troponin T (TnT) and troponin C (TnC) form the troponin complex of the thin filaments of striated muscle. TnI is acts as the inhibitory subunit by blocking actin-myosin interactions and thereby mediating striated muscle relaxation. The TnI subfamily contains 3 genes: TnI-skeletal-fast-twitch, TnI-skeletal-slow-twitch, and TnI-cardiac. The TNNI3 gene encodes the TnI-cardiac protein and is exclusively expressed in cardiac muscle tissues. Mutations in the TNNI3 gene cause familial hypertrophic cardiomyopathy type 7 (CMH7) and familial restrictive cardiomyopathy (RCM).

Discoidin Domain Receptor Tyrosine Kinase 1 (DDR1) is a transmembrane glycoprotein which is a part of the discoidin-like domain containing subfamily of receptor tyrosine kinases. DDR1 functions as cell surface receptor for fibrillar collagen and regulates cell attachment to the extracellular matrix, remodeling of the extracellular matrix, cell migration, differentiation, survival and cell proliferation. DDR1 is expressed in epithelial cells, mainly in the kidney, lung, gastrointestinal tract, and brain and is significantly overexpressed in several human tumors.

Dickkopf-related protein 2 (DKK2) is a member of the dickkopf family, which has a vital role in vertebrate development, where they locally inhibit Wnt regulated processes such as antero-posterior axial patterning, limb development, somitogenesis and eye formation. In adults, Dkks are involved in bone formation and bone disease, cancer and Alzheimer disease. DKK2 contains 2 cysteine rich regions and is implicated in embryonic development through its interactions with the Wnt signaling pathway. DKK2 may function as either an agonist or antagonist of Wnt/beta-catenin signaling, depending on the cellular environment and the presence of the co-factor kremen 2. DKK2 protein activity is also controlled by binding to the Wnt co-receptor LRP6 (LDL-receptor related protein 6).

M-phase inducer phosphatase 1 (CDC25A) belongs to the CDC25 family of phosphatases. CDC25A is essential for progression from G1 to the S phase of the cell cycle. CDC25A activates the cyclin-dependent kinase CDC2 by eliminating 2 phosphate groups. CDC25A is specifically degraded in reaction to DNA damage, which inhibits cells with chromosomal abnormalities from progressing in the course of cell division. CDC25A is an oncogene, though its exact function in oncogenesis has not been determined.

Killer Cell Lectin-like Receptor Subfamily G, Member 1 (KLRG1) is a member of the killer cell lectin-like receptor (KLR) family, which is a group of transmembrane proteins preferentially expressed in NK cells. Natural killer (NK) cells are lymphocytes which mediate lysis of certain tumor cells and virus-infected cells without previous activation. NK cells can also regulate specific humoral and cell-mediated immunity. The cell surface expression of KLRG1 is up-regulated by MHC class I molecules expression.

CTDSP1 is a class 2C phosphatase with activity dependent on the conserved DxD motif. CTDSP1 preferentially catalyzes the dephosphorylation of 'Ser-5' within the tandem 7 residues repeats in the C-terminal domain (CTD) of the largest RNA polymerase II subunit POLR2A. In addition, CTDSP1 negatively regulates RNA polymerase II transcription, possibly by controlling the transition from initiation/capping to processive transcript elongation.

Connective Tissue Growth Factor is a part of the CCN family of proteins. The CCN family presently consists of six members in human also known as: Cyr61 (Cystein rich 61), CTGF, Nov (Nephroblastoma Overexpressed gene), WISP-1, 2 and 3 (Wnt-1 Induced Secreted Proteins). 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: tumorigenesis,fibrosis and vascular ailments. 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 4 modules: Module I shares partial identity with the N-terminal part of the Insulin-like Growth Factor Binding Proteins (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.
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.

Ornithine decarboxylase is the preliminary and rate-limiting enzyme in the biosynthetic pathway of polyamines and it takes part in the alteration of ornithine to putrescine. ODC1 is a key member of various biological processes, such as cell growth, transformation, differentiation and apoptosis. Overexpression of the ODC1 gene has a vital part in cell proliferation and the progress of cancer.

FK506 Binding Protein 5 (FKBP5) belongs to the immunophilin protein family, which has a role in immunoregulation and basic cellular processes involving protein folding and trafficking. FKBP5 is a cis-trans prolyl isomerase, which binds to the immunosuppressants FK506 and rapamycin. FKBP5 is an immunophilin protein with PPIase and co-chaperone activities. FKBP5 is assumed to mediate calcineurin inhibition. FKBP5 is a component of unligated steroid receptors heterocomplexes through interaction with heat-shock protein 90 (HSP90). In addition, FKBP5 interacts functionally with mature hetero-oligomeric progesterone receptor complexes along with the 90 kDa heat shock protein and P23 protein.

ErbB3, also called Her3 (human epidermal growth factor receptor 3), is a type I membrane glycoprotein that is a member of the ErbB family of tyrosine kinase receptors. ErbB family members serve as receptors for the epidermal growth factor (EGF) family of growth factors. Among ErbB family members, ErbB3 is unique in that it contains a defective kinase domain. ErbB3 is expressed in keratinocytes, melanocytes, skeletal muscle cells, embryonic myoblasts and Schwann cells. Monomeric ErbB3 serves as a low affinity receptor for the heregulins (HRG). ErbB3 can induce specific antibody production in vivo, hence to inhibit tumor cell growth. ErbB-3 can be used to treat early, medium and advanced or post-operative breast cancer with over-expression of ErbB2. According to its mechanism of action, ErbB3 is classified as a therapeutic for cancer.

Cystatin E/M or CST6 is part of the cystatin type 2 family. Part of the cystatin type 2 family members can act as cysteine protease inhibitors, whereas cystatin E/M regulates cathepsin B inhibitors and not cathepsin C. cystatin E/M is a protein the when secreted, has an effect on osteogenesis and bone resorption, insulin regulation, response to systemic inflammation & hepatocyte growth factor receptors.

SPINT2 is a transmembrane protein acts as an inhibitor of HGF activator. SPINT2 inhibits plasmin, plasma and tissue kallikrein, and factor XIa. SPINT2 has two extracellular Kunitz domains that inhibit few serine proteases. SPINT2 is assumed tumor suppressor, mutations in SPINT2 leads to a congenital sodium diarrhea.

Carbohydrate Sulfotransferase 10, also known as CHST10 is a member of the sulfotransferase 2 family. CHST10 was first recognized as a sulfotransferase which acts on the human natural killer-1 (HNK-1) glycan. Furthermore, CHST10 is a carbohydrate involved in neurodevelopment as well as synaptic plasticity.

BCA-1 is a CXC chemokine that is highly expressed in thesecondary lymphoid organs, such as follicles of the spleen, lymph nodes, and Peyer's patches. CXCL13 promotes the migration of B lymphocytes (compared to T cells and macrophages), by stimulating calcium influx into, and chemotaxis of, cells expressing Burkitt's lymphoma receptor 1 (BLR1). BCA1 therefore function in the homing of B lymphocytes to follicles. Human BCA-1 shares a 64% amino acid sequence similarity with the mouse protein and 23 - 34% amino acid sequence identity with other known CXC chemokines. Recombinant or chemically synthesized BCA1 is a potent chemoattractant for B lymphocytes but not T lymphocytes, monocytes or neutrophils. BLR1, a G protein-coupled receptor originally isolated from Burkitt’s lymphoma cells, has now been shown to be the specific receptor for BCA1. Among cells of the hematopoietic lineages, the expression of BLR-1, now designated CXCR-5, is restricted to B lymphocytes and a subpopulation of T helper memory cells.

HECT and RLD Domain Containing E3 Ubiquitin Protein Ligase 5 (HERC5) is a member of the HERC family of ubiquitin ligases, found in a cluster of HERC family genes on chromosome 4. HERC5 is a protein with a HECT domain and 5 RCC1 repeats. The HERC5 protein localizes to the cytoplasm and perinuclear region and serves as an INF-induced E3 protein ligase that mediates ISGylation of protein targets. HERC5 exhibits antiviral activity towards HIV-1, influenza A virus and human papillomavirus. HERC5 is a major E3 ligase for ISG15 conjugation. HERC5 also serves as a positive regulator of innate antiviral response in cells induced by INF. Pro-inflammatory cytokines upregulate HERC5 in endothelial cells. HERC5 is physically connected with polyribosomes, broadly modifies recently synthesized proteins in a cotranslational fashion.

Secernin 1 (SCRN1) which is a member of the peptidase C69 family, regulates exocytosis in mast cells. SCRN1 increases both the level of secretion and the sensitivity of mast cells to stimulation with calcium.

Fractalkine soluble form is chemotactic for t-cells and monocytes, but not for neutrophils. Fractalkine membrane-bound form promotes adhesion of those leukocytes to endothelial cells. Fractalkine regulates leukocyte adhesion and migration processes at the endothelium and binds to CX3CR1. Natural Human Fractalkine is produced as a long protein (373-amino acid) with an extended mucin-like stalk and a chemokine domain on top. The mucin-like stalk permits it to bind to the cell surface. Fractalkine gene is located on human chromosome 16 along with some CC chemokines known as CCL17 and CCL22.

Latexin enzyme is a carboxypeptidase A inhibitor that is highly expressed in the heart, prostate, ovary, kidney, pancrease, brain and colon. Latexin has no noticeable sequence resemblance with plant and parasite inhibitors, however it is related to a human putative tumor suppressor protein, TIG1. Latexin is down-regulated in the presenilin-1-deficient mouse brain, thus putatively playing a role in Alzheimer's disease.

Chloride channels are various group of proteins that control fundamental cellular processes including stabilization of cell membrane potential, transepithelial transport, regulation of intracellular pH, and maintenance of cell volume. CLIC1 is part of the p64 family and is localized to the cell nucleus. CLIC1 displays both nuclear and plasma membrane chloride ion channel activity. CLIC1 inserts into membranes and forms chloride ion channels. CLIC1 channel activity depends on the pH. CLIC1 membrane insertion is redox-regulated and happens under oxydizing conditions.

Crystallin Zeta, also known as CRYZ, Binds NADP and participates in a one-electron transfer process. CRYZ takes part in the detoxification of xenobiotics and Interacts with (AU)-rich elements (ARE) in the 3'-UTR of target mRNA species. CRYZ improves the mRNA coding for BCL2.

PCMT1 enzyme catalyses the methyl esterification of L-isoaspartyl and D-aspartyl residues in peptides and proteins that result from spontaneous decomposition of normal L-aspartyl and L-asparaginyl residues. PCMT1 is involved in the repair and/or degradation of damaged proteins.

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.

Aldo-keto reductase family 1 member C1 or AKR1C1 is an enzyme, part of the aldo/keto reductase family that holds over 40 familiar proteins. AKR1C1 promotes the conversion of ketones & aldehydes to their alcohol forms by using cofactors such as NADH & NADPH. AKR1C1 promotes the progesterone reduction to its inactive molecule form 20-alpha-hydroxy-progesterone.