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tRNA-splicing endonuclease subunit Sen15 (TSEN15) is a member of the SEN15 family. tRNA splicing is an essential process required for cell growth and division. TSEN15 is a subunit of the tRNA splicing endonuclease. TSEN15 cleaves pre-tRNA at the 5' and 3' splice sites to release the intron.

Polypeptide N-Acetylgalactosaminyltransferase 1 (Galnt1) , is part of the UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase (GalNAc-T) family of enzymes. The initial reaction in O-linked oligosaccharide biosynthesis is catalyzed by Glant1, the transfer of an N-acetyl-D-galactosamine residue to a serine or threonine residue on the protein receptor. Moreover, Galnt1 is implicated in the glycosylation of proteins vital for bone formation for instance osteopontin and bone sialoprotein.

Neuron-specificenolase also caled NSE is a glycolytic isoenzyme which is situated in central and peripheral neurons and neuroendocrine cells. Enolase-2 is released into the CSF when neural tissue is injured. Neoplasms derived from neural or neuroendocrine tissue release Enolase-2 into the blood. Enolase-2 is a useful substance that has been detected in patients with certain tumors, such as neuroblastoma, small cell lung cancer, medullary thyroid cancer, carcinoid tumors, pancreatic endocrine tumors, and melanoma. ENO2 is 1 of the 3 enolase isoenzymes found in mammals. ENO2 isoenzyme, is found in mature neurons and cells of neuronal origin. An exchange from alpha enolase to gamma enolase occurs in neural tissue during development in rats and primates.

Threonyl-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 83 kDa protein is an autoantigen recognized by PL-7 antibodies which occur in a subset of patients with polymyositis and dermatomyositis. Preliminary data suggest that PL-7 antibodies (similar to Jo-1 antibodies) indicate an increased risk for lung involvement, but this needs to be confirmed for a larger number of cases.

MAO-B is a member of the flavin monoamine oxidase family. MAO-B (Monoamine oxidase B) is a flavin-containing mitochondrial enzyme that catalyzes the oxidative deamination of biogenic and xenobiotic monoamines. MAO-B controls the metabolic degradation of catecholamines and serotonin in neural and other target tissues. MAO-B is located in platelets and in DOPA-secreting neurons in the brain. MAOB and MAOA genes have an imperative function in DOPA degradation. Benzylamine and phenylethylamine are preferentially degraded by MAOB. The MAOB gene is linked to autistic traits, empathy and Asperger syndrome. Amplified levels of MAO B are identified in the brain of Alzheimer’s patients. High phenylethylamine levels in neonates as a result of low MAOB are consistent with phenylketonuria in newborns. Polymorphisms in MAO-B are connected to smoking behavior.

Prostaglandin Reductase 1 (PTGR1) is a member of the NADP-dependent oxidoreductase L4BD family. PTGR1 catalyzes the conversion of leukotriene B4 into its biologically less active metabolite, 12-oxo-leukotriene B4, thus being a primary step of metabolic inactivation of leukotriene B4. PTGR1 is highly expressed in the kidney, liver, and intestine but not in leukocytes.

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.

Hydroxyacid Oxidase 1 (HAO1) is a part of the superfamily of the alpha hydroxy acid oxidases (HAO) enzymes. HAO1 catalyses the FMN mediated oxidation of glycolate to glyoxylate and glyoxylate to oxalate by reducing oxygen to hydrogen peroxide. HAO1 is expressed mainly in the liver and pancreas and is most active on twocarbon substrates such as glycolate. HAO1 isthe main cause of hyperoxaluria, a disorder in which large deposits of calcium oxalate form kidney stones.

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.

Methionyl Aminopeptidase 1D (METAP1D) is a part of the peptidase M24A family. METAP1D which is overexpressed in colon cancer cell lines participates in tumorigenesis. METAP1D eliminates methionine from the N-terminus of nascent proteins.

Membrane Metalloendopeptidase, also known as MME is a zinc metallopeptidase which is expressed at the cell surface of various cells. MME degrades the amyloid beta peptide whose abnormal misfolding as well as aggregation in neural tissue has been implicated as the cause for Alzheimer's disease. MME is expressed in an extended range of tissues and is especially plentiful in the kidney. MME is also a common acute lymphocytic leukemia antigen which is a significant cell surface marker in the diagnosis of human acute lymphocytic leukemia (ALL). MME is used in hematological diagnosis because it is expressed by early B, pro-B and pre-B lymphocytes, and also by lymph node germinal centers.

Epoxide Hydrolase 1 Microsomal (EPHX1) is a vital biotransformation enzyme which transfers epoxides from the degradation of aromatic compounds to trans-dihydrodiols that can be conjugated and excreted from the body. Epoxide hydrolase plays a role in both activation and detoxification of epoxides. Mutations in EPHX1 trigger preeclampsia, epoxide hydrolase deficiency or increased epoxide hydrolase activity.

Dual Specificity Phosphatase 22, also known as DUSP22, is a part of the protein-tyrosine phosphatase family which holds 1 tyrosine-protein phosphatase domain. DUSP22 activates the Jnk signaling pathway and dephosphorylates and deactivates p38 and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK). DUSP22 interacts with MAPK1 and MAPK8.

Mitochondrial methylglutaconyl-CoA hydratase (AUH) is involved in the amino acid degradation pathway by catalyzing the conversion of 3-methylglutaconyl-CoA to 3-hydroxy-3-methylglutaryl-CoA and water. AUH Human is expressed as a single mRNA species of 1.8 kb, and translated as a 40kDa precursor protein which is consequently processed to a 32kDa mature form. AUH has a very low enoyl-CoA hydratase activity. The AUH protein binds to the AU-rich element (ARE), which is a common element found in the 3' UTR of rapidly decaying mRNA such as c-fos, c-myc and granulocyte/ macrophage colony stimulating factor. AU-rich elements are involved in directing RNA to rapid degradation and deadenylation. In addition, AUH is homologous to enol-CoA hydratase, which is an enzyme involved in fatty acid degradation, and has been shown to have intrinsic hydratase enzymatic activity. AUH is therefore a bifunctional chimera between RNA binding and metabolic enzyme activity.

L-threonine to glycine degradation consists of a two-step biochemical pathway which involvs the enzymes L-threonine dehydrogenase and 2-amino-3-ketobutyrate coenzyme A ligase. L-Threonine is initially converted into 2-amino-3-ketobutyrate by L-threonine dehydrogenase. Glycine C-Acetyltransferase (GCAT) is the 2nd enzyme in this pathway, which subsequently catalyzes the reaction between 2-amino-3-ketobutyrate and coenzyme A to form glycine and acetyl-CoA. The GCAT enzyme is regard as a class II pyridoxal-phosphate-dependent aminotransferase. GCAT is strongly expressed in the heart, brain, liver and pancreas. GCAT is also found in lung.

TPI1 is one of the triosephosphate isomerase family. TPI1 catalyzes the isomerization of glyceraldehydes 3-phosphate (G3P) and dihydroxy-acetone phosphate (DHAP) in glycolysis and gluconeogenesis. Mutations in TPI1 causes triosephosphate isomerase deficiency (TPI deficiency). TPI deficiency is an autosomal recessive disorder which is the most severe clinical disorder of glycolysis and is related to neonatal jaundice, chronic hemolytic anemia, progressive neuromuscular dysfunction, cardiomyopathy and increased susceptibility to infection.

IMPDH1 is a rate limiting enzyme in the de novo synthesis of guanine nucleotides and consequently participates in the regulation of cell growth. IMPDH1 takes part in the development of malignancy and the growth progression of some tumors. IMPDH1 performs as a homotetramer to regulate cell growth. IMPDH1 catalyzes the synthesis of xanthine monophosphate (XMP) from inosine-5''-monophosphate (IMP). Defects in this gene are a cause of retinitis pigmentosa type 10 (RP10).

Ectonucleotide Pyrophosphatase-2, aka ENPP2, a part of the ectonucleotide pyrophosphatasefamily. ENPP2 is able to cut the phosphodiester bond between the alpha and the beta position of triphosphate nucleotides, acting as an ectonucleotide phosphodiesterase producing pyrophosphate, as most members of the ENPP family. It is unlike ENPP-1 and ENPP-3, has weak activity against nucleotides, but shows a lysophospholipase D activity which allows the formation of LPA and choline from lysophosphatidylcholine. As well, ENPP-2 and LPA are involved in several inflammatory-driven diseases such as arthritis and asthma.

DPP4 also called adenosine deaminase complexing protein-2, and T-cell activation antigen CD26 is a serine exopeptidase and complex enzyme that is expressed on the surface of most cell types. DPPIV is an intrinsic membrane glycoprotein and a serine exopeptidase that cleaves X-proline dipeptides from the N-terminus of polypeptides. DPP4 plays a role in t-cell activation. DPP4 is associated with intracellular signal transduction, apoptosis and involved in tumor biology. There are at least 63 substrates which can bind specifically to DPP4 enzyme including growth factors, chemokines, neuro peptides. Furthermore, DPP4 plays a major role in glucose metabolism by cleaving incretins such as glucose-dependent insulinotropic polypeptide (GIP) and GLP-1.

Kallikreins are a subgroup of serine proteases having various physiological functions. Numerous kallikreins are involved in carcinogenesis. Kallikrein-11 (KLK11) which is a multifunctional protease is 1 of the 15 kallikrein subfamily members found in a cluster on chromosome 19. KLK11 cleaves synthetic peptides after arginine but not lysine residues.

DCXR catalyzes the NADPH-dependent reduction of numerous pentoses, tetroses, trioses, alpha-dicarbonyl molecules and L-xylulose. DCXR takes part in the uronate cycle of glucose metabolism. DCXR participates in the water absorption and cellular osmoregulation in the proximal renal tubules by producing xylitol, an osmolyte, thus preventing osmolytic stress from occurring in the renal tubules.

Hexokinases phosphorylate glucose to produce glucose-6-phosphate, thus committing glucose to the glycolytic pathway. Alternative splicing of Glucokinase results in three tissue-specific forms of glucokinase, one found in pancreatic islet beta cells and two found in liver. The protein localizes to the outer membrane of mitochondria. In contrast to other forms of hexokinase, HK4 is not inhibited by its product glucose-6-phosphate but remains active while glucose is abundant. Mutations in this gene have been associated with non-insulin dependent diabetes mellitus (NIDDM), maturity onset diabetes of the young, type 2 (MODY2) and persistent hyperinsulinemic hypoglycemia of infancy (PHHI).

AHCY is an enzyme that catalyzes the reversible hydrolysis of S-adenosylhomocysteine (AdoHcy) to adenosine (Ado) and L-homocysteine (Hcy). AHCY controls the intracellular S-adenosylhomocysteine (SAH) concentration that is crucial for transmethylation reactions. AHCY deficiency causes hypermethioninemia.

Aldolase C Fructose-Bisphosphate (ALDOC) belongs to the class I fructose-bisphosphate aldolase family. ALDOC is a glycolytic enzyme which catalyzes the reversible aldol cleavage of fructose-1,6-biphosphate and fructose 1-phosphate to dihydroxyacetone phosphate and either glyceraldehyde-3-phosphate or glyceraldehydes respectively. ALDOC is expressed exclusively in the hippocampus and Purkinje cells of the brain.