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PSMB1 is part of the proteasome B-type family, also identified as the T1B family, that is a 20S core beta subunit. PSMB1 is tightly linked to the TBP (TATA-binding protein) gene in human and in mouse, and is transcribed in the opposite orientation in both species.The main function of PSMB1 is its degradation activity of unnecessary or damaged proteins by proteolysis. PSMB1 is a multicatalytic proteinase complex which is characterized by its ability to cleave peptides with arg, phe, tyr, leu, and glu adjacent to the leaving group at neutral or slightly basic ph. the proteasome has an atp-dependent proteolytic activity.

GSK3B is a serine-threonine kinase that belongs to the glycogen synthase kinase subfamily. GSK3B is involved in energy metabolism, neuronal cell development, and body pattern formation. Polymorphisms in the GSK3B gene have been implicated in modifying risk of Parkinson disease, and studies in mice show that overexpression of the GSK3B gene may be significant to the pathogenesis of Alzheimer disease.

PTP4A2 is part of a small class of the protein tyrosine phosphatase (PTP) family. PTP4A2 is localized to the early endosome that take part in a variety of cellular activities. PTP4A2 protein interacts with the beta-subunit of Rab geranylgeranyltransferase II (beta GGT II), therefore has a role as a regulator of GGT II activity. Overexpression of PTP4A2 in mammalian cells conferred a transformed phenotype, which suggested its role in tumorigenesis.

Canopy FGF Signaling Regulator 1, also known as CNPY1, is expressed in the midbrain-hindbrain (MHB) boundary in zebrafish. CNPY1, which binds FGFR1, also takes part in FGF signaling.

Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes. All VEGF-receptors have seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular split tyrosine kinase domain. VEGFR-2 has a lower affinity for VEGF than the Flt-1 receptor, but a higher signaling activity. Mitogenic activity in endothelial cells is mainly mediated by VEGFR-2 leading to their proliferation.
Differential splicing of the flt-1 gene leads to the formation of a secreted, soluble variant of VEGFR-1 (sVEGFR-1). No naturally occuring, secreted forms of VEGFR-2 have so far been reported. The binding of VEGF165 to VEGFR-2 is dependent on heparin.

Vesicular overexpressed in cancer prosurvival protein 1 (VOPP1) has been previously shown to be over-expressed in human glioblastoma multiform and squamous cell carcinoma. VOPP1 is a crucial regulator of NF-kappaB signaling, and this high-level, amplification-mediated VOPP1 expression, such as that occurring in tumors with amplified EGFR, might impact the resistance to apoptosis.

HAUS augmin-like complex subunit 1 (HAUS1) is 1 of 8 subunits of the 390kDa human augmin complex/ HAUS complex. The augmin complex is a microtubule-binding complex required in microtubule generation within the mitotic spindle and is imperative to mitotic spindle compilation. HAUS1 contributes to mitotic spindle assembly, maintenance of centrosome integrity and completion of cytokinesis as part of the HAUS augmin-like complex. HAUS1 is broadly expressed, especially in the pancreas, kidney, skeletal muscle, liver and heart. However it is weakly expressed in the lung, brain and placenta. HAUS1-depleted cells hold functional cell cycle checkpoints, but the depletion reduces the G2/M cell cycle compartment and stimulates apoptosis. The HAUS1 protein level remains constant through the cell cycle.

Growth/differentiation factors (GDF1-GDF15) belong to the BMP family of TGF-beta superfamily proteins. These factors are produced as inactive preproproteins which are subsequently cleaved and assembled into active secreted homodimers. BMP13 is a growth factor which controls proliferation and cellular differentiation in the retina and bone formation. BMP13 has a central role in regulating apoptosis during retinal development. GDF proteins are vital during embryonic development, particularly in the skeletal, nervous, and muscular systems. BMP13 gene mutations result in colobomata, which are congenital abnormalities in ocular development, and in Klippel-Feil syndrome (KFS), which is a congenital disorder of spinal segmentation.

The conserved 76 amino acid protein ubiquitin (Ub) regulates a host of intracellular processes through its enzymatic conjugation to other cellular proteins.
Ubiquitination occurs through sequential steps catalyzed by activating (E1), conjugating (E2), and ligase (E3) enzymes. The final step results in the formation of an isopeptide bond between Ub’s C-terminal glycine residue (G76) and a lysine residue of the target protein, although N-terminal ubiquitination is also known.
Outcomes of this modification include destabilization of the conjugated protein, altered protein trafficking and functional modulation.
After targeting the protein for specific localizations, ubiquitin is released from the substrate by deubiquitinating enzymes.
A mutant ubiquitin, having a Gly to Ala substitution at the C-terminus (G76A ubiquitin) supported several downstream reactions of the proteolytic pathway but inhibits the deubiquitination process.
As consequence, the Ub derivative becomes irreversibly conjugated to protein, shifting the equilibrium between the bound and unbound form in the direction of conjugation, at the expense of the free form.

Glucagon receptor is part of the glucagon receptor family which also contains GLP-1, GLP-2, GHRH and GIP receptors. GCGR regulates blood glucose levels and is mainly expressed in the pancreas, liver and kidneys. Mutations in GCGR are a cause of non-insulin-dependent diabetes mellitus.

TNFSF12 is a cytokine that is part of the TNF ligand family. TNFSF12 is a ligand for the FN14/TWEAKR receptor. TNFSF12 has overlapping signaling functions with TNF, but displays a much wider tissue distribution. TNFSF12 induces apoptosis through multiple pathways of cell death in a cell type-specific manner. TNFSF12 promotes proliferation and migration of endothelial cells, and therefore acts as a regulator of angiogenesis. TNFSF12 is expressed in adult heart, pancreas, skeletal muscle, small intestine, spleen and peripheral blood lymphocytes. TWEAK h induces NFkB and chemokine secretion. TNFSF12 exerts an apoptotic activity in HT-29 human adenocarcinoma cells whilst cultured in the presence of IFN-?. TNFSF12 promotes proliferation and migration of endothelial cells.

ACAT2 enzyme participates in lipid metabolism. ACAT2 takes part in lipoprotein assembly, catalyzing cholesterol esterification in mammalian cells. ACAT2 is an integral membrane protein that localizes to the endoplasmic reticulum of human intestinal cells. ACAT2 deficiency contributes to severe mental retardation and hypotonus.

Acyl-CoA Thioesterase 7 (ACOT7) belongs to the acyl coenzyme family. ACOT7 hydrolyzes the CoA thioester of palmitoyl-CoA and other long-chain fatty acids. Decreased expression of the ACOT7 protein may be linked to mesial temporal lobe epilepsy.

Cystatins are a superfamily of cysteine proteinase inhibitors found in both plants and animals. They comprise a group of proteinase inhibitors, widely distributed in tissues and body fluids, and form tight complexes with cysteine proteases such as cathepsin B, H, L and S. Cystatin C, a secreted molecule of this family, is of interest from biochemical, medicine and evolutionary points of view. Cystatin C, with molecular weight of 13260 Da, is composed of 120 amino acids, lacks carbohydrate and has two disulfide bridges located near the carboxyl terminus. Cystatin C is increased in patients with malignant diseases, and is related to the insufficiency of renal function and appears to be a better marker than creatinine. On the other hand, low levels of cystatin C involve cause the breakdown of the elastic laminae and, subsequently, the atherosclerosis and abdominal aortic aneurysm.

The cytokine Macrophage migration inhibitory factor (MIF) has been identified to be secreted by the pituitary gland and the monocyte/macrophage and to play an important role in endotoxic shock. MIF has the unique property of being released from macrophages and T cells in response to physiological concentrations of glucocorticoids. The secretion of MIF is tightly regulated and decreases at high, anti-inflammatory steroid concentration.

CCL23 (MIP-3) is a ligand for the CCR1chemokine receptor. CCL23 is one of several cytokine genes clustered on the q-arm of chromosome 17, in a locus containing several other CC chemokines. MIP-3 chemoattracts monocytes, resting T-lymphocytes and neutrophils, but not activated lymphocytes. Furthermore, it was shown that MIP-3 inhibits colony formation of bone marrow myeloid immature progenitors. MIP-3 is mainly expressed in lung and liver tissue, but can be also found in bone marrow and placenta, as well as in some cell lines of myeloid origin.
Alternative splicing of the CCL23 gene produces 2 mRNAs which encode a short (CK?8) and a long (CK?81) isoform of the MIP-3. CK?8 cDNA encodes a 120 amino acid residue precursor protein with a putative 21 a.a. residue signal peptide which is cleaved to generate a 99 a.a. residue mature CK?8 (a.a. 22-120). Further N-terminal processing of the 99 a.a. residue variant can produce a 75 a.a. residue CK?8 (a.a. 46-120) which is considerably more active than the 99 a.a. residue variant.
MIP-3 may be involved in the malignant progression of certain human cancer cells which overexpress ErbB2 through the transactivation of ErbB2 tyrosine kinase. MIP-3 may also be involved in angiogenesis via upregulation of matrix metalloproteinase MMP-2 expression.

Cathepsin-Z (CTSZ) is a lysosomal cysteine proteinase and member of the peptidase C1 family. CTSZ, which has been also known as cathepsin X and cathepsin P, exhibits carboxy-monopeptidase and carboxy-dipeptidase activities. CTSZ is expressed ubiquitously in cancer cell lines and primary tumors and, similar to other members of this family, takes part in tumorigenesis.

Hepatocyte Growth Factor (HGF) is a multifunctional growth factor which regulates both cell growth and cell motility. It exerts a strong mitogenic effect on hepatocytes and primary epithelial cells. HGF synergizes with Interleukin-3 and GM-CSF to stimulate colony formation of hematopoietic progenitor cells in vitro and may, therefore, also modulate hematopoiesis.

Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and assist in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit (MRPL13 is a 39S subunit protein) and have an estimated 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed. An additional difference between mammalian mitoribosomes and prokaryotic ribosomes is that the second contain a 5S rRNA. Among various species, the proteins comprising the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, which prevents easy recognition by sequence homology.

SCG3 belongs to the chromogranin/secretogranin family of neuroendocrine secretory proteins. Though, the function of SCG3 is unknown, Granins operate as precursors for biologically active peptides. Several granins are known to serve as helper proteins in sorting and proteolytic processing of prohormones.

Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and help in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit and have about 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed. Mitochondrial Ribosomal Protein S2 (MRPS2) is a 28S subunit protein which is a part of the ribosomal protein S2 family and comprises a 12S rRNA and about 30 distinct proteins.

AKR1C3 is part of the aldo/keto reductase superfamily, which has at least 40 identified proteins. AKR1C3 catalyzes the conversion of aldehydes and ketones to their corresponding alcohols by utilizing NADH and/or NADPH as cofactors. AKR1C3 displays overlapping but distinct substrate specificity. AKR1C3 catalyzes the reduction of prostaglandin (PG) D2, PGH2 and phenanthrenequinone (PQ), and the oxidation of 9alpha,11beta-PGF2 to PGD2. AKR1C3 is involved in the pathogenesis of allergic diseases such as asthma. AKR1C3 controls cell growth and/or differentiation. AKR1C3 takes part in adrenal testosterone production. AKR1C3 expression is affected by metabolic disease, and its levels are considerably reduced in response to diet-induced weight loss and correlate with leptin levels.

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.

DDB1-and CUL4-associated factor (DCAF7) is involved in craniofacial development. The DCAF7 protein acts upstream of the EDN1 pathway and is essential for formation of the upper jaw equivalent, the palatoquadrate. The activity necessary for the EDN1 pathway function varies between the first and second arches. DCAF7 associates with DIAPH1 and controls GLI1 transcriptional activity. DCAF7 may be involved in normal and diseased skin development.