Search results

GGCT is a member of the family of transferases, specifically the aminoacyltransferases. GGCT protein catalyzes the formation of 5-oxoproline from gamma-glutamyl dipeptides and takes an important part in glutathione homeostasis. GGCT induces release of cytochrome c from mitochondria with resultant induction of apoptosis.

Creatine Kinase, Mitochondrial 2 (CKMT2) is a member of the ATP:guanido phosphotransferase family. CKMT2 is responsible for the transfer of high energy phosphate from mitochondria to the cytosolic carrier, creatine. CKMT2 reversibly catalyzes the transfer of phosphate between ATP and various phosphogens (e.g. creatine phosphate). Creatine kinase isoenzymes have a principal role in energy transduction in tissues with large, variable energy demands, such as skeletal muscle, heart, brain and spermatozoa. Mitochondrial creatine kinase occurs in 2 different oligomeric forms: dimers and octamers, contrary to the exclusively dimeric cytosolic creatine kinase isoenzymes. The CKMT2 gene contains sequences homologous to a number of motifs which are shared among some nuclear genes encoding mitochondrial proteins and therefore may be crucial for the coordinated activation of these genes during mitochondrial biogenesis.

Set 7/9 is a histone methyltransferase (HMTase) that transfers methyl groups to Lys4 of histone H3, in complex with S-adenosyl-L-methionine (AdoMet). The methylation of lysine residues of histones plays a critical role in the regulation of chromatin structure and gene expression.
Acetylation, phosphorylation and methylation of the amino-terminal tails of histone are thought to be involved in the regulation of chromatin structure and function. The enzymes identified in the methylation of specific lysine residue on histones belong to the SET family with just one exception. Set7/9, unlike most other SET proteins, is exclusively a mono-methylase.

RNHA is an endonuclease which specifically degrades the RNA of RNA-DNA hybrids. Localized to the nucleus, the RNHA protein mediates the removal of Okazaki fragment RNA primers which are present on the lagging strand during DNA replication. RNHA catalyzes the endonucleolytic cleavage of RNA to a 5'-phosphomonoester and is capable of binding magnesium or manganese as cofactors.

Arylsulfatase A (ARSA) hydrolyzes cerebrosidesulfate to cerebroside and sulfate. ARSA is inhibited by phosphate. The phosphate develops a covalent bond with the active site 3-oxoalanine. ARSA gene defects cause metachromatic leucodystrophy (MLD), a progressive demyelination disease which results in various neurological symptoms and ultimately death.

Glutamine--Fructose-6-Phosphate Transaminase 1 (GFPT1) participates in the hexosamine pathway and controls the glucose fluidity into the hexosamine pathway. GFPT1 regulates the availability of precursors for N- and O-linked glycosylation of proteins. GFPT1 controls the circadian expression of clock genes ARNTL/BMAL1 and CRY1.

Arginase-1 is part of the urea cycle, it catalyzes the hydrolysis of arginine to ornithine and urea. There are two isoforms of mammalian arginase which differ in their tissue location, subcellular localization, immunologic crossreactivity & physiologic role. Arginase-1is a cytosolic enzyme and expressed primarily in the liver tissue. Inherited deficiency in this enzyme may lead toargininemia, which is an autosomal recessive disease in which hyperammonemia is detected.

Heparanase is an endo β-D-glucuronidase, which degrades heparan sulfate side chains of heparan sulfate proteoglycans (HSPGs) in the extracellular matrix. Heparanase plays an important role in ECM degradation, facilitating the migration and extravasation of tumor cells and inflammatory leukocytes (1,2,3). Upon degradation, heparanase releases growth factors and cytokines that stimulate cell proliferation and chemotaxis (4,5). Heparanase is a heterodimer comprised of a 50 kDa subunit harboring the active site and a 8 kDa subunit. It is produced as a latent 65 kDa precursor and proteolytically processed to its active form (1,6). Heparanase is highly expressed in myeloid leukocytes (i.e. neutrophils) in platelets and in human placenta. Human heparanase was found to be upregulated in various types of primary tumors, correlating in some cases with increased tumor invasiveness and vascularity and with poor prospective survival (7,8).

Cathepsin-Z (CTSZ) is a lysosomal cysteine proteinase and a member of the peptidase C1 family. CTSZ, which is known also 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 as other members of this family, takes part in tumorigenesis.

Arylsulfatase A (ARSA) hydrolyzes cerebrosidesulfate to cerebroside and sulfate. ARSA is inhibited by phosphate. The phosphate develops a covalent bond with the active site 3-oxoalanine. ARSA gene defects cause metachromatic leucodystrophy (MLD), a progressive demyelination disease which results in various neurological symptoms and ultimately death.

Nicotinamide Nucleotide Adenylyltransferase 2, also known as NMNAT2 is a member of the nicotinamide mononucleotide adenylyltransferase (NMNAT) enzyme family, members of which catalyze a vital step in NAD (NADP) biosynthetic pathway. Unlike the other human family member, which is localized to the nucleus, and is ubiquitously expressed; NMNAT2 is cytoplasmic, and is predominantly expressed in the brain. Two transcript variants encoding different isoforms have been found for NMNAT2. Among the diseases associated with NMNAT2 are tauopathy, and systemic lupus erythematosus.

N-terminal Xaa-Pro-Lys N-methyltrasferase1, also known as NTMT1 belongs to the methyltransferase superfamily. NTMT1 catalyzesthe transfer of the methyl group from the S-adenosyl-l-methionine to the protein ?-amine, resulting in the formation of S-adenosyl-l-homocysteine and ?-N-methylated proteins. NTMT1 is a remarkable potential anticancer targetsince it is overexpressed in gastrointestinal cancers in addition to his essential function in cell mitosis.

Alanyl-tRNA synthetase is a member of the aminoacyl-tRNA synthetase family, key enzymes of protein biosynthesis which charge tRNA molecules with the respective amino acids. This 108 kDa protein is an autoantigen recognized by PL-12 antibodies which occur in a subset of patients with polymyositis and dermatomyositis. Preliminary data suggest that epitope spreading occurs in the autoimmune PL-12 response such that even antibodies to an isolated alanyl-tRNA molecule can develop.

Beta-1,3-N-Acetylglucosaminyltransferase 2 (B3GNT2) is a part of the beta-1,3-N-acetylglucosaminyltransferase family which takes part in the synthesis of poly-N-acetyllactosamine. B3GNT2 is a type II transmembrane protein which prefers the substrate of lacto-N-neotetraose. B3GNT2 catalyzes the initiation and elongation of poly-N-acetyllactosamine chains and comprises the main polylactosamine synthase.

E3 ubiquitin-protein ligase SIAH1 (SIAH1) belongs to the SIAH (seven in absentia homolog) family. SIAH1 is a tumor suppressor protein, which is expressed in intestinal epithelium and activated during apoptosis. SIAH1 is involved in ubiquitination and proteasome-mediated degradation of specific proteins. SIAH1 is comprised of an N-terminal RING-finger domain (required for proteolysis) and a cystein-rich C-terminal domain (which regulates oligomerization and SIAH binding to target proteins). SIAH1 causes indirect degradation of beta-catenin by way of creation of a complex with Siah-interacting protein (SIP), Skp1 and Ebi.

Caspase 3 Apoptosis-Related Cysteine Peptidase (CASP3) belongs to the cysteine-aspartic acid protease (caspase) family. Sequential activation of caspases plays a key role in the execution-phase of cell apoptosis. Caspases exist as inactive proenzymes which undergo proteolytic processing at conserved aspartic residues to generate 2 subunits, large and small, that dimerize to create the active enzyme. CASP3 protein cleaves and activates caspases 6, 7 and 9, and the protein itself is processed by caspases 8, 9 and 10. CASP3 is the leading caspase involved in the cleavage of amyloid-beta 4A precursor protein, which is linked with neuronal death in Alzheimer's disease. In addition, CASP3 is involved in the cleavage of huntingtin. CASP3 also cleaves and activates sterol regulatory element binding proteins (SREBPs) between the basic helix-loop-helix leucine zipper domain and the membrane attachment domain. CASP3 initiates cell adhesion in sympathetic neurons through RET cleavage.

PDXK converts vitamin B6 to Pyridoxal-5-phosphate (PLP), which is a vital cofactor in the intermediate metabolism of amino acids and neurotransmitters. PDXK is cytoplasmic and probably acts as a homodimer. The biological validity of the alternatively spliced transcript variants has not been determined.

N-6 Adenine-Specific DNA Methyltransferase 1, also known as N6AMT1 is part of the methyltransferase family. N6AMT1 is implicated in the methylation of release factor I during translation termination. In addition, N6AMT1 is involved in converting the arsenic metabolite monomethylarsonous acid to the less toxic dimethylarsonic acid.

DARS uses a 2 step reaction to catalyze the specific attachment of an amino acid to its cognate tRNA: the amino acid (AA) is first activated by ATP to form AA-AMP and then transferred to the acceptor end of the tRNA.

GlpK also known as glycerol kinase, is a member of the FGGY kinase family. GlpK catalyzes the transfer of a phosphate group from ATP to glycerol, thereby forming glycerol phosphate. Furthermore, this intermediate can then be converted to dihydroxyacetone phosphate (DHAP), which is utilized in either glycolysis or gluconeogenesis. The activity of GlpK is affected by numerous metabolites. The non-competitive allosteric inhibition by fructose 1,6-bisphosphate (FBP) triggers modifications in the quaternary structure of Glpk.

BLMH is affiliate to the papain superfamily of the cysteine protease and the peptidase C1 family. BLMH is a cytoplasmic cysteinepeptidase usually found as a homohexamer. The standard physiological role of BLMH has not been determined, but it shields normal and malignant cells from the glycopeptide antitumor drug BLM. BLMH catalyzes the inactivation of the antitumor drug BLM (a glycopeptide) by hydrolyzing the carboxyamide bond of its B-aminoalaninamide moiety and in addition demonstrates general aminopeptidase activity.

GUK1 is part of the guanylate kinase family. GUK1 occurs as a monomer that catalyzes the ATP-dependent conversion of GMP to GDP, thus takes an important part in the recycling of GMP. Through its catalytic activity, GUK1 functions in regulation of the supply of guanine nucleotides to signal transduction pathways. GUK1 overexpression is related with pituitary adenocarcinomas, implicating that GUK1 is has a role in tumorigenesis.

Aldo-keto reductase family 1 member D1 (AKR1D1) belongs to the AKR superfamily. The AKR family proteins are soluble NADPH oxidoreductases, which have vital roles in the metabolism of drugs, carcinogens and reactive aldehydes. AKR1D1 is also responsible for the catalysis of the 5-beta-reduction of bile acid intermediates and steroid hormones that carry a delta (4)-3-1 structure. AKR1D1 is highly expressed in the liver, colon and testis. Deficiency of the AKR1D1 enzyme may contribute to hepatic dysfunction.