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This gene is a member of the EPO/TPO family and encodes a secreted, glycosylated cytokine composed of four alpha helical bundles. The protein is found in the plasma and regulates red cell production by promoting erythroid differentiation and initiating hemoglobin synthesis. This protein also has neuroprotective activity against a variety of potential brain injuries and antiapoptotic functions in several tissue types.

The Fas receptor (CD95) mediates apoptotic signaling by Fas-ligand expressed on the surface of other cells. The Fas-FasL interaction plays an important role in the immune system and lack of this system leads to autoimmunity, indicating that Fas-mediated apoptosis removes self-reactive lymphocytes. Fas signaling is also involved in immune surveillance to remove transformed cells and virus infected cells. Binding of FAS to oligimerized FasL on another cell activates apoptotic signaling through a cytoplasmic domain termed the death domain that interacts with signaling adaptors including FAF, FADD and DAX to activate the caspase proteolytic cascade. Caspase-8 and caspase-10 are first activated, to then cleave and activate downstream caspases, and a variety of cellular substrates that lead to cell death. Caspases cleave nuclear lamins, causing the nucleus to break down and lose its normal structure and another caspase substrate is DFF, inducing cleavage and degradation of the genome. Other caspase substrates are involved in cytoskeletal structure, cell cycle regulation and signaling pathways. Activation of JNK kinase, activation of Jun, and production of ceramide may also play roles in Fas-mediated apoptosis. Activation of fas-mediated apoptosis is opposed by I-FLICE and FAP. Viruses and tumors may escape immune surveillance in part through suppression of fas-mediated apoptosis using similar mechanisms.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

Calnexin (CANX) belongs to the calnexin family of molecular chaperones. Calnexin is a calcium-binding, ER-associated protein that interacts briefly with newly synthesized N-linked glycoproteins, facilitating protein folding and assembly. Calnexin may also have a key role in the quality control of protein folding by retaining incorrectly folded protein subunits within the ER for degradation. Calnexin grants long-term protection of wild-type Shaker protein from ER-associated degradation. Polypeptide substrate recognition by Calnexin requires specific conformations of the Calnexin protein. Calnexin dwindles with aging and might contribute to a cytoprotection in an array of human age-related diseases.

CAPSL is a calcium-binding protein holding two conserved calcium-binding motifs (EF-hands) which are found in a superfamily of calcium sensors and calcium signal modulators. In addition, the CAPSL gene is in the same linkage disequilibrium (LD) block as the IL7R gene and there is well known association between the CAPSL-IL7R locus and type 1 diabetes.

Members of the IFN regulatory factor (IRF) family regulate gene expression critical to immune response, hemopoiesis, and proliferation. IRF-3 is a member of the IRF family, and is distinct from other family members. Its transcriptional activity is regulated solely by posttranslational modifications. It plays a crucial role in activation of innate immunity and inflammation in response to viral infection. IRF-3 mediates IFN-stimulated response element (isre) promoter activation. Functions as a molecular switch for antiviral activity. Dsrna generated during the course of an viral infection leads to IRF3 phosphorylation on the c-terminal serine/threonine cluster. This induces a conformational change, leading to its dimerization, nuclear localization and association with creb binding protein (crebbp) to form dsrna-activated factor 1 (draf1), a complex which activates the transcription of genes under the control of isre. The complex binds to the ie and prdiii regions on the ifn-alpha and ifn-beta promoters respectively. IRF-3 does not have any transcription activation domains.

PRDX3 is part of the peroxiredoxin family of antioxidant enzymes, that reduces hydrogen peroxide and alkyl hydroperoxides. PRDX3 is particularly located in the mitochondria and involved in the regulation of cellular redox status by serving as a primary line of defense against H2O2 produced during respiration. PRDX3 is a significant regulator of the abundance of mitochondrial H(2)O(2), which itself promotes apoptosis in cooperation with other mediators of apoptotic signaling. PRDX3 mitochondrial protein is significantly decreased in Alzheimer Disease and Down Syndrome.

Microfibrillar-associated protein 4 (MFAP4) is a member of Fibrinogen protein family and contains 1 fibrinogen C-terminal domain. The MFAP4 protein has similarity to a bovine microfibril-associated protein. MFAP4 has binding specificities for both collagen and carbohydrate. MFAP4 is believed to be an extracellular matrix protein that is involved in cell adhesion or intercellular interactions. MFAP4 deletion was found in 30 of 31 Smith-Magenis syndrome (SMS) patients.

NANS is a 359 amino acid protein that contains one AFP (antifreeze proteins)-like domain and functions in the biosynthesis of sialic acids. The ubiquitously expressed NANS enzymatically catalyzes the H2O-dependent formation of N-acetylneuraminic acid (Neu5Ac) and 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (KDN), both of which are sialic acids. NANS uses N-acetylmannosamine 6-phosphate as a substrate for Neu5Ac synthesis and mannose 6-phosphate as a substrate for KDN synthesis.

ENO1 is a homodimeric soluble protein that encodes a smaller monomeric structural lens protein, tau-crystallin. ENO1 is a glycolytic enzyme expressed in mainly all tissues. ENO1 isoenzyme full length protein is found in the cytoplasm. The shorter protein is formed from another translation start that is restricted to the nucleus, and binds to a component in the c-myc promoter. ENO1 is involved in anaerobic metabolism under hypoxic conditions and plays a role as a cell surface plasminogen receptor during tissue invasion. Irregular expression of Enolase-1 is linked with tumor progression in several cases of breast and lung cancer. Enolase-1 is as an auto antigen associated with Hashimoto's encephalopathy and severe asthma. ENO1 is the target protein of serum anti-endothelial antibody in Behcet's disease.

Phosphomevalonate kinase (PMVK) is a cytosolic enzyme. PMVK is expressed highly in the heart, liver, skeletal muscle, kidney and pancreas and slightly lower in the brain, placenta, and lung. PMVK catalyzes the conversion of mevalonate 5-phosphate into mevalonate 5-diphosphate in the fifth reaction of the cholesterol biosynthetic pathway. Induced by sterol, PMVK participates in isopentenyl diphosphate biosynthesis via the mevalonate pathway.

Thioredoxin-2 is a low molecular weight redox protein. TRX2 contains a redox active disulfide/dithiol group within the conserved Cys-Gly-Pro-Cys active site. The TXN2 is involved in the regulation of the mitochondrial membrane potential and in protection against oxidant-induced apoptosis. Upon stimulation of Fas, TXN2 mediates denitrosylation of mitochondria-associated caspase-3, a process required for caspase-3 activation, and promoted apoptosis.
TRX2 is important at low oxidative stress conditions.
MTRX is involved in the regulation of the mitochondrial membrane potential and cell death. Mitochondrial thioredoxin plays an important roles in protection against oxidant-induced apoptosis. Thioredoxin1 and thioredoxin2 have opposed regulatory functions on hypoxia-inducible factor-1alpha.

CRK belongs to the signaling adapter protein family which binds to several tyrosine-phosphorylated proteins. CRK is involved in many cellular processes such as apoptosis, proliferation, and differentiation. CRK has a modular domain architecture consisting of an SH2 followed by two SH3 domains (src-homology domains). The N-terminal SH2 domain of the CRK protein functions as a positive regulator of transformation whereas the C-terminal SH3 domain functions as a negative regulator of transformation.

MRPS25, a 28S subunit protein, is a member of the ribosomal protein S5P family. An equivalent pseudogene is located on chromosome 4.

ANGPTL3 and ANGPTL4 are angiopoietin-like proteins secreted and expressed mainly by the liver, their role being the regulation of triglyceride metabolism by inhibiting the lipolysis of triglyceride-rich lipoproteins. During different nutritional states (feeding/fasting) the levels of the circulating triglycerides are regulated by Angptl3 and Angptl4 through differential inhibition of Lipoprotein lipase (LPL) as shown by the experimental data. The molecular structure of ANGPTL3 is similar to that of the angiopoietins (vascular endothelial growth factors). Deletion mutants of human Angiopoietin 5 were used in order to demonstrate that the N-terminal domain (fragment 17-207) and not the C-terminal fibrinogen-like domain (fragment 207-460) increased the plasma triglyceride levels in mice.

Human HSP40 (heat shock protein with molecular size of 40kDa) is one of the mammalian homologues of bacterial DnaJ heat shock protein and regulates cellular processes by aiding in the folding, transport and assembly. HSP40 protein contains the J-domain which controls interaction with the ATPase domain of DnaK.

SSU72 is an extremely conserved homologue of yeast Ssu72, a CTD phosphatase and a component of the polyadenylation/termination machinery. SSU72 interacts with TFIIB, Rb and DNAM-1 and operates to catalyze the dephosphorylation of target proteins, and taking part in RNA processing and termination via dephosphorylation of Pol II. SSU72 is found in multiple alternatively spliced isoforms.

Inositol monophosphatase1 (IMPA1) is responsible for the provision of inositol essential for synthesis of phosphatidylinositol and polyphosphoinositides. IMPA1 has a central role in the phosphatidylinositol signaling pathway by catalyzing the hydrolysis of inositol monophosphates. IMPA1 has been recognized as the pharmacological target for lithium action in the brain. The IMPA1 enzyme has a magnesium-dependent phosphatase activity and is inhibited by therapeutic concentrations of lithium. Inhibition of inositol monophosphate hydroylosis and ensuing depletion of inositol for phosphatidylinositol synthesis may perhaps explain the anti-manic and anti-depressive effects of lithium administered to treat bipolar disorder.

FKBP6 is part of the immunophilin protein family, and is involved in immunoregulation and basic cellular functions involving protein folding and trafficking. FKBP6 is widely expressed in all tissues, FKBP6 is present at utmost levels in testis, liver, kidney, skeletal muscle and heart. Deletion of FKBP6 contributes to hypercalcemia and growth delay in Williams-Beuren syndrome.

CD14 (also known lipopolysaccharide (LPS) receptor) is expressed strongly on monocytes and macrophage and weakly on the surface of neutrophils. CD14 is anchored to cells by linkage to glycosylphosphatidylinositol (GPI) and functions as a high affinity receptor for complexes of LPS and LPS binding protein (LBP). Soluble CD14, also binding to LPS, acts at physiological concentration as an LPS agonist and has, at higher concentrations, an LPS antagonizing effect in cell activation. CD14 has been shown to bind apoptotic cells.

GALE is an enzyme that participates as the third enzyme in the Leloir pathway of galactose metabolism. GALE is a homodimeric epimerase localized in bacterial, plant, and mammalian cells. GALE inhances the reverse chemical reaction, the conversion of UDP-glucose to UDP-galactose. UDP-galactose builds galactose-containing proteins and fats, which have a crucial part in chemical signaling, building cellular structures, transporting molecules, and producing energy.

TPMT, thiopurine S-methyltransferase, is a cytosolic enzyme that metabolizes thiopurine drugs via S-adenosyl-L-methionine as the S-methyl donor and S-adenosyl-L-homocysteine as a byproduct. TPMT activity exhibits autosomal codominant genetic polymorphism, and patients inheriting TPMT-deficiency are at high risk of potentially fatal hematopoietic toxicity.