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Aminoacyl-tRNA synthetases are a class of enzymes that charge tRNAs with their cognate amino acids. The protein encoded by this gene is a cytoplasmic enzyme which belongs to the class II family of aminoacyl-tRNA synthetases. The enzyme is responsible for the synthesis of histidyl-transfer RNA, which is essential for the incorporation of histidine into proteins. The gene is located in a head-to-head orientation with HARSL on chromosome five, where the homologous genes share a bidirectional promoter. The gene product is a frequent target of autoantibodies in the human autoimmune disease polymyositis/dermatomyositis.

DECR1 is a mitochondrial protein which exists as a homotetramer and is a member of a family of short-chain dehydrogenases/reductases. DECR1 acts as an auxiliary enzyme of beta-oxidation andt partakes in the metabolism of unsaturated fatty enoyl-CoA esters. in particular, DECR1 uses NADP+ to catalyze the reduction of 2,4-dienoyl-CoA to yield trans-3-enoyl-CoA that can subsequently be used as an intermediate in the Krebs cycle. Furthermore, DECR1 is believed to work as a tumor suppressor, possibly downregulating the expression of Neu and slowing the rate of tumorigenesis.

HECT and RLD Domain Containing E3 Ubiquitin Protein Ligase 5 (HERC5) is a member of the HERC family of ubiquitin ligases, found in a cluster of HERC family genes on chromosome 4. HERC5 is a protein with a HECT domain and 5 RCC1 repeats. The HERC5 protein localizes to the cytoplasm and perinuclear region and serves as an INF-induced E3 protein ligase that mediates ISGylation of protein targets. HERC5 exhibits antiviral activity towards HIV-1, influenza A virus and human papillomavirus. HERC5 is a major E3 ligase for ISG15 conjugation. HERC5 also serves as a positive regulator of innate antiviral response in cells induced by INF. Pro-inflammatory cytokines upregulate HERC5 in endothelial cells. HERC5 is physically connected with polyribosomes, broadly modifies recently synthesized proteins in a cotranslational fashion.

Monoamine Oxidase A, also known as MAOA catalyzes the oxidative deamination of biogenic as well as xenobiotic amines and has significant functions in the metabolism of neuroactive and vasoactive amines in the central nervous system as well as peripheral tissues. Mutation in MAOA results in Brunner syndrome; in addition MAOA has also been linked with a diversity of other psychiatric disorders, which includes antisocial behavior. MAOA preferentially oxidizes biogenic amines such as 5-hydroxytryptamine (5-HT).

Death effector domain-containing protein (DEDD) is a cytoplasmic protein. The cell death activity of DEDD relates to its nuclear localization. DEDD translocates to the nucleus during CD95-mediated apoptosis, there it localizes to nucleoli-like structures, activates caspase-6 and particularly inhibits RNA polymerase I-dependent transcription. DEDD is usually expressed in a variety of tissues, and found in the highest levels in the testis. Overexpression of DEDD was shown to induce weak apoptosis.

Tyrosyl-tRNA synthetase (YARS2) is a mitochondrial protein which catalyzes the attachment of tyrosine to tRNA(Tyr) in a two-step reaction: tyrosine is first activated by ATP to form Tyr-AMP and afterward transferred to the acceptor end of tRNA(Tyr). YARS2 gene mutations are linked with myopathy with lactic acidosis and sideroblastic anemia type 2 (MLASA2).

Ribonuclease 1R (NASE1) is a small protein which is a part of pancreatic ribonuclease enzyme family. NASE1 has 4 disulfide bonds in its native state and cleaves speciallyafter pyrimidine nucleotides.Cleavage takes place in 2 steps: first, the 3’,5’-phosphodiester bond is cleaved to craete a 2’,3’-cyclic phosphodiester intermediate; than, the cyclic phosphodiester is hydrolyzed to a 3’-monophosphate. NASE1is activated the most with single stranded RNA.NASE1inhibited by alkylation of His12 and His119 and activated by potassium and sodium salts.NASE1hydrolyzes RNA from protein samples.

GLUL catalyzes the synthesis of glutamine from glutamate and ammonia. Glutamine is a major source of energy and that takes part in cell proliferation, inhibition of apoptosis, and cell signaling. GLUL is expressed during early fetal stages, and has a role in maintaining body pH by removing ammonia from circulation. Mutations in GLUL gene are related with congenital glutamine deficiency.

HEXA is the alpha subunit of the lysosomal enzyme beta-hexosaminidase which, combined with the cofactor GM2 activator protein, catalyzes the degradation of the ganglioside GM2, and other molecules having N-acetyl hexosamines terminus. The two subunits composing Beta-hexosaminidase, alpha and beta, belong to the glycosyl hydrolases family and are encoded by distinct genes. Alpha subunit gene mutations can cause Tay-Sachs disease (GM2-gangliosidosis type I).

CA8 was first called CA-related protein since there is a sequence similarity to other identified carbonic anhydrase genes. Still, this protein has no carbonic anhydrase activity - the reversible hydration of carbon dioxide. CA8 still holds a carbonic anhydrase designation due to obvious sequence similarity to other members of the carbonic anhydrase gene family. Mutations in CA8 result in cerebellar ataxia mental retardation and dysequilibrium syndrome type 3 (CMARQ3).

Phosphoglycolate phosphatase (PGP) is discovered in all tissues including red cells, lymphocytes and cultured fibroblasts (at protein level). PGP is most active in skeletal muscle and cardiac muscle. The catalytic activity of PGP is 2-phosphoglycolate + H2O = glycolate + phosphate. Diseases associated with PGP include tardive dyskinesia and polycystic kidney disease.

Ubiquitin-conjugating enzyme E2 R2 (UBE2R2) is a member of the ubiquitin-conjugating enzyme family. Protein kinase CK2 is a ubiquitous and pleiotropic Ser/Thr protein kinase implicated in cell growth andtransformation. This protein is a protein similar to the E2 ubiquitin conjugating enzyme UBC3/CDC34. Studies propose that CK2-dependent phosphorylation of this ubiquitin-conjugating enzyme functions by regulating beta-TrCP substrate recognition and induces its interaction with beta-TrCP, enhancing beta-catenin degradation. UBE2R2 receives ubiquitin from the E1 complex and catalyzes its covalent attachment to other proteins. In vitro catalyzes monoubiquitination and 'Lys-48'-linked polyubiquitination. UBE2R2 may be implicated in degradation of katenin. Among the diseases associated with UBE2R2 are cblc, and herpes simplex.

Human Ubquitin-conjugating enzyme 7 (UbcH7) is a ubiquitin-conjugating enzyme (E2) mediating c-fos degradation, transcription factor NF-B maturation, and human papilloma virus-mediated p53 and Myc protein degradation, in vitro. The ubiquitin-conjugating enzymes (E2s) are essential components of the post-translational protein ubiquitination pathway, mediating the transfer of activated ubiquitin to substrate proteins. The human UBE2L1-UBE2L4 gene could potentially encode different isoforms of the UbcH7. UBE2L3 gene, located at chromosome 22q11.2, is the only identical family member with introns and encodes a polypeptide sequence identical to that of UbcH7.

UBE2K belongs to the ubiquitin-conjugating enzymes family which take part in many cellular processes such as selective protein degradation, DNA repair, cell cycle control, and sporulation. In this mechanism, the ATP-coupled activation and subsequent ligation of ubiquitin are catalyzed by separate enzymes functionally linked by ubiquitin carrier protein UBC1. In addition, UBE2K is involved in Alzheimer's disease, Huntington's disease and antigen processing through its interaction with amyloid-?, huntingtin, and MHC-heavy chain proteins.

GlsA1 is a member of the great superfamily of serine-dependent beta-lactamases and penicillin-binding proteins which exist almost in every bacteria and eukaryotes and catalyze the hydrolytic deamidation of l-glutamine to l-glutamate and free NH4+.

Acetyl-COA Acyltransferase 2, (ACAA2) is a member of the thiolase family. ACAA2 catalyzes the final step of the mitochondrial fatty acid beta-oxidation spiral. Not like most mitochondrial matrix proteins, ACAA2 contains a non-cleavable amino-terminal targeting signal.

G/U mismatch-specific DNA glycosylase (mug) is a part of the TDG/mug DNA glycosylase family. Mug is necessary for DNA damage lesion repair in stationary-phase cells. Mug protein removes three N4-ethenocytosine and takes away s the uracil base from mismatches in the order of U:G>U:A. The enzyme Uracil-N-Glycosylase removes uracil from the DNA leaving an AP position. Mug is also able to hydrolyzing the carbon-nitrogen bond among the sugar-phosphate backbone of the DNA and the mispaired base. The complementary strand guanine plays a role in substrate recognition.

ALDOB is a tetrameric glycolytic enzyme which catalyzes the reversible cleavage of fructose 1-phosphate into dihydroxyacetone phosphate and glyceraldehyde. Fructose-bisphosphate aldolase B (ALDOB) is one of 3 known aldolase isoenzymes, and is located in the kidney and the small adult intestine where it is linked with aldolases A or C. ALDOB is regulated by Insulin and glucagon and is implicated in hereditary fructose intolerance disease.

CTDSP1 is a class 2C phosphatase with activity dependent on the conserved DxD motif. CTDSP1 preferentially catalyzes the dephosphorylation of 'Ser-5' within the tandem 7 residues repeats in the C-terminal domain (CTD) of the largest RNA polymerase II subunit POLR2A. In addition, CTDSP1 negatively regulates RNA polymerase II transcription, possibly by controlling the transition from initiation/capping to processive transcript elongation.

Acid Phosphatase-2, also known as ACP2 is composed of two subunits, Alpha & beta, and is chemically as well as genetically distinct from red cell acid phosphatase. ACP2 belongs to a family of distinct isoenzymes which hydrolyze orthophosphoric monoesters to alcohol and phosphate. In addition, Acid phosphatase deficiency is caused by mutations in the ACP2-beta subunit as well as ACP3-alpha subunit genes.

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.

GLUL catalyzes the synthesis of glutamine from glutamate and ammonia. Glutamine is a major source of energy and that takes part in cell proliferation, inhibition of apoptosis, and cell signaling. GLUL is expressed during early fetal stages, and has a role in maintaining body pH by removing ammonia from circulation. Mutations in GLUL gene are related with congenital glutamine deficiency.

Phosphomannomutase 1 (PMM1) is an enzyme involved in the synthesis of the GDP-mannose and dolichol-phosphate-mannose required for a number of critical mannosyl transfer reactions. PMM1 catalyzes the conversion between D-mannose 6-phosphate and D-mannose 1-phosphate which is a substrate for GDP-mannose synthesis. GDP-mannose is used for the synthesis of dolichol-phosphate-mannose, which is crucial for N-linked glycosylation and accordingly the secretion of several glycoproteins as well as for the synthesis of glycosyl-phosphatidyl-inositol (GPI) anchored proteins. Additionally, PMM1 may be responsible for the degradation of glucose-1,6-bisphosphate in ischemic brain.