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MAPKSP1 is a scaffold protein which operates in the extracellular signal-regulated kinase (ERK) cascade. MAPKSP1 protein is restricted to late endosomes by the mitogen-activated protein-binding protein-interacting protein, and binds specifically to MAP kinase kinase MAP2K1/MEK1, MAP kinase MAPK3/ERK1, and MAP kinase MAPK1/ERK2.

Ectodysplasin A Receptor, also known as EDAR belongs to the tumor necrosis factor receptor family. EDAR is a receptor for the soluble ligand ectodysplasin A, and is capable of activating the nuclear factor-kappaB, JNK, as well as caspase-independent cell death pathways. EDAR is necessary for the development of hair, teeth, and other ectodermal derivatives. Furthermore, mutations in EDAR resulted in autosomal dominant and recessive forms of hypohidrotic ectodermal dysplasia.

MAT2A is an important enzyme in cellular metabolism and catalyzes the formation of S-adenosylmethionine (SAMe) from L-methionine and ATP. MAT2A is expressed in extrahepatic tissues. In liver, MAT2A expression associates with growth, dedifferentiation, and cancer. NF-kappa B and AP-1 are necessary for basal MAT2A expression in HepG2 cells and mediate the increase in MAT2A expression in response to TNF-alpha. Up-regulation of MAT2A provides growth improvement and s-adenosylmethionine and methylthioadenosine thus can block mitogenic signaling in colon cancer cells. Lower expression of both MAT2A and MAT2beta and interfere with leptin signaling in liver cancer cells.

Neutral endopeptidase (NEP) is an enzyme located in the cell membrane (bound to it) that is able to dissolve biologically active proteins and is expressed on the surface of lymphoid progenitors, human podocytes, syncytiotrophoblastic cells, and many other epithelial cells including polymorphonuclear leukocytes.

HER-2/neu (erbB-2) encodes an 185-kDa orphan receptor tyrosine kinase that is constitutively active as a dimer and displays potent oncogenic activity when overexpressed. Herstatin, as the product of alternative HER-2 transcript, retains intron 8.
The herstatin mRNA is expressed in normal human fetal kidney and liver, but is at reduced levels relative to p185HER-2 mRNA in carcinoma cells that contain an amplified HER-2 gene. Herstatin appears to be an inhibitor of p185HER-2, because it disrupts dimers, reduces tyrosine phosphorylation of p185, and inhibits the anchorage-independent growth of transformed cells that overexpress HER-2.

Scavenger mRNA-decapping enzyme (DCPS) is a member of the HIT family. DCPS is required for the complete degradation of mRNAs, both in normal mRNA turnover and in nonsense-mediated mRNA decay. It was shown that DCPS hydrolyzes the residual m7GpppN cap structure after the complete 3'–5' degradation of the mRNA by the exosome. Furthermore, DCPS releases m7GMP and is incapable of cleaving cap structures attached to a long RNA chain.

BAT1 belongs to the DEAD box family of RNA-dependent ATPases that mediate ATP hydrolysis during pre-mRNA splicing. UAP56 protein is a vital splicing factor which is needed for connecting U2 small nuclear ribonucleoprotein with pre-mRNA, as well as takes a key part in mRNA export from the nucleus to the cytoplasm. Mutations in this protein may be connected to rheumatoid arthritis.

Endonuclease III (nth) is a DNA repair enzyme which has both DNA N-glycosylase activity and AP-lyase activity. The DNA N-glycosylase activity releases numerous damaged pyrimidines from DNA by cleaving the N-glycosidic bond and leaving an AP (apurinic/apyrimidinic) site. This AP-lyase activity cleaves the phosphodiester bond 3' to the AP site by a beta-elimination, thus leaving a 3'-terminal unsaturated sugar and a product with a terminal 5'-phosphate.

NUDT3 is a 172 amino acid cytoplasmic protein which is a member of the nudix hydrolase family and DIPP subfamily. NUDT3 functions as a negative regulator of the ERK 1/2 pathway and hydrolyzes 5-phosphoribose 1-diphosphate. NUDT3 is a monomer which binds magnesium as a cofactor. In addition, NUDT3 is widely expressed but can be found at highest levels in the liver, pancreas, brain and heart.

RNA Guanylyltransferase And 5'-Phosphatase also known as RNGTT is a bifunctional mRNA-capping enzyme which exhibits RNA 5'-triphosphatase activity in the N-terminal section and mRNA guanylyltransferase activity in the C-terminal section. In addition, RNGTT catalyzes the first two steps of cap formation, through removing the gamma-phosphate from the 5'-triphosphate end of nascent mRNA to yield a diphosphate end, and also by transferring the gmp moiety of GTP to the 5'-diphosphate terminus.

BDNF promotes the survival of neuronal populations that are all located either in the central nervous system or directly connected to it. BDNF is a major regulator of synaptic transmission and plasticity at adult synapses in many regions of the cns. The versatility of BDNF is emphasized by its contribution to a range of adaptive neuronal responses including long-term potentiation (ltp), long-term depression (ltd), certain forms of short-term synaptic plasticity, as well as homeostatic regulation of intrinsic neuronal excitability.

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.

N-acylneuraminate-9-phosphatase (NANP) belongs to the haloacid dehalogenase (HAD) family and is responsible for dephosphorylating N-acylneuraminate 9-phosphate to form N-acylneuraminate (N-acylneuraminate 9-phosphate + H2O = N-acylneuraminate + phosphate). The catalytic activity of NANP is relies on the presence of magnesium and is inhibited by vanadate and calcium, which is typical of the HAD phosphatase family.

NCK1 is an adapter protein which binds with tyrosine-phosphorylated growth factor receptors or their cellular substrates. NCK1 maintains low levels of EIF2S1 phosphorylation by promoting its dephosphorylation by PP1. NCK1 is involved in the DNA damage response, for efficient activation of downstream effectors, such as that of CHEK2. NCK1 is one of the signaling and transforming proteins containing Src homology 2 and 3 (SH2 and SH3) domains. NCK1 is located in the cytoplasm and is an adaptor protein that participates in transducing signals from receptor tyrosine kinases to downstream signal recipients such as RAS.

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.

RAC1 is a GTPase which belongs to the RAS superfamily of small GTP-binding proteins. Members of this superfamily appear to regulate a diverse array of cellular events, including the control of cell growth, cytoskeletal reorganization, and the activation of protein kinases. RAC-1 regulates the actin cytoskeleton but also other cellular processes. RAC1 have been shown to be involved in the regulation of cell-cell adhesion.

Dual Specificity Phosphatase 26 (DUSP26) inhibits MAP kinase p38 by dephosphorylating it and inhibits p38-mediated apoptosis in anaplastic thyroid cancer cells. DUSP26 also induces activation of MAP kinase p38 and c-Jun N-terminal kinase. DUSP26 inactivates MAPK1 and MAPK3 which leads to dephosphorylation of heat shock factor protein 4 and a decrease in its DNA-binding activity.

Branched-chain ?-keto acid dehydrogenase E1 component ? chain (BCKDHA) is a member of the BCKDHA family. The BCKD (branched-chain alpha-keto acid dehydrogenase) complex is an inner mitochondrial enzyme complex which catalyzes the second major step in the catabolism of the branched-chain amino acids leucine, isoleucine, and valine. This complex consists of 3 catalytic components: a heterotetrameric (alpha2-beta2) branched-chain alpha-keto acid decarboxylase (E1), a dihydrolipoyl transacylase (E2), and a dihydrolipoamide dehydrogenase (E3). Mutations in the BCKDHA gene result in maple syrup urine disease, type IA.

L-Asparaginase is an enzyme that depletes L-Asparagine "an important nutrient for cancer cells" resulting in cancer/tumor cell starvation. L-asparaginase is an anti-tumor agent derived from E.coli.,which can inhibit the growth of malignant cells. It is used mainly for the induction of remission in acute lymphoblastic leukaemia. Because of the lymph node origin of malignant B cells in Multiple Myeloma, L-Asparagine is an essential amino acid for their cell metabolism, and, consequently, L-Asparaginase may be of value in managing the disease.
The rationale behind asparaginase is that it takes advantage of the fact that ALL cellsare unable to synthesize the non-essential amino acidasparaginewhereas normal cells are able to make their own asparagine. These leukemic cells depend on circulating asparagine. Asparaginase however catalyzes the conversion of L-asparagine to aspartic acidand ammonia. This deprives the leukemic cell of circulating asparagine.

Apoptosis-Inducing Factor, Mitochondrion-Associated, 1 (AIFM1) is a mitochondrial protein which translocates to the nucleus once apoptosis has been initiated. AIFM1 causes DNA fragmentation and chromatin condensation and also triggers the release of cytochrome c and caspase-9 from mitochondria. Bcl-2 overexpression prevents the release of AIFM1 from mitochondria, but doesn’t block its apoptogenic activity.

Cathepsin D is synthesized as a 54kDa precursor, which is proteolytically processed to an intermediate 48kDa single chain, which matures into more stable 34kDa and 14kDa two chain form. It is an estrogen-regulated lysosomal protease that has been suggested to facilitate cancer cell migration and invasion by digesting the basement membrane, extracellular matrix, and xonnective tissue. Because of its mitogenic and proteolytic activities, it has been implicated as a prognostic marker in many tumor types. Cathepsin D is expressed in epithelial cells as well as in macrophages.

DUSPs are distinguished by their ability to dephosphorylate both tyrosine and serine/threonine residues. DUSPs have been implicated as major modulators of critical signaling pathways. Dual specificity phosphatase 19 (DUSP19) belongs to the dual specificity protein phosphatase subfamily. DUSP19 is a protein phosphatase which functions as a stress-activated protein kinase pathway-regulating phosphatase. DUSP19 contains a variation of the consensus DUSP C-terminal catalytic domain, with the last serine residue replaced by alanine, and lacks the N-terminal CH2 domain found in the MKP class of DUSPs.

PPCDC is a member of the HFCD (homo oligomeric flavin containing Cys decarboxylase) superfamily which takes a part in the biosynthesis of coenzyme A (CoA) from pantothenate (Vitamin B). The biosynthesis of CoA from pantothenate needs several steps: the phosphorylation of pantothenate, the conversion of 4’-hosphopantothenate to 4''-phosphopantetheine, the adenylation by phosphopantetheine adenylyltransferase to form dephospho-CoA and the phosphorylation by dephospho-CoA kinase to form CoA. PPCDC is a key player in this pathway. PPCDC converts 4''-phosphopantothenate into 4''-phosphopantetheine.

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, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.