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GABARAPL2 takes part in intra Golgi traffic and modulates intra Golgi transport by coupling between NSF activity and SNAREs activation. GABARAPL2 first stimulates the ATPase activity of NSF which in turn stimulates the association with GOSR1.

Placental alkaline phosphatase also known as PLAP is a membranal siaglycoprotein enzyme typicallyfoundin high concentration in syncytiotrophoblasts in the placenta amid the 3th trimester of gestation. The expression of PLAP was at firstconsidered to be onlyin the term placenta, though, a human PLAP-like variant has been found,thathas more than 85% homology with PLAP itself. PLAP is expressed strictly in normal term placenta, endocervix & fallopian tube and in ovarian and proximal gastrointestinal tumors. It is also widely expressed in germ cell tumors and more recently found in seminomas.

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.

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.

OAS1 enzyme is a member of the 2’,5’-oligoadenylate synthetase family. OAS1 is induced by interferons and uses adenosine triphosphate in 2’-specific nucleotidyl transfer reactions to synthesize 2’,5’-oligoadenylates(2-5As). These molecules in turn activate latent RNase L resulting in viral RNA degradation and the inhibition of viral replication.
OAS1 may have a role in mediating resistance to virus infection, control of cell growth, differentiation, and apoptosis. OAS1 binds double-stranded RNA and polymerizes ATP into PPP (A2'P5'A)N oligomers, which activate the latent RNase L that, once activated, cleaves single-stranded RNAs.
OAS1 gene mutations are been linked to host susceptibility to viral infection.
OSA1 gene polymorphisms are linked to the outcome of hepatitis C virus infection. Furthermore, OAS1 gene polymorphisms are linked to the susceptibility to severe acute respiratory syndrome.

Ectonucleotide Pyrophosphatase (ENPP1) belongs to the ecto-nucleotide pyrophosphatase/phosphodiesterase (ENPP) family. ENPP1 is a type II transmembrane glycoprotein comprised of 2 identical disulfide-bonded subunits. The ENPP1 protein has broad specificity and cleaves various substrates, including phosphodiester bonds of nucleotides and nucleotide sugars and pyrophosphate bonds of nucleotides and nucleotide sugars. The ENPP1 protein can hydrolyze nucleoside 5' triphosphates to their corresponding monophosphates and it may also hydrolyze diadenosine polyphosphates. ENPP1 gene mutations are linked with 'idiopathic' infantile arterial calcification and ossification of the posterior longitudinal ligament of the spine (OPLL).

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.

Acid Phosphatase-6, also known as ACP6 is Hydrolyzes lysophosphatidic acid (LPA) which contains a medium length fatty acid chain to the corresponding monoacylglycerol. ACP6 shows highest activity with lysophosphatidic acid which contains myristate (C14:0), monounsaturated oleate (C18:1) or palmitate (C16:0), and lower activity with C18:0 as well as C6:0 lysophosphatidic acid.

Mercaptopyruvate Sulfurtransferase (MPST) catalyzes the transfer of a sulfur ion from 3-mercaptopyruvate to cyanide or other thiol compounds. MPST might be involved in cysteine degradation and cyanide detoxification. The MPST enzyme is regulated by oxidative stress and thioredoxin. In oxidative stress conditions, the catalytic cysteine site is transformed to a sulfenate which inhibits the MPST enzyme activity. The reduced thioredoxin cleaves an intersubunit disulfide bond to activate the redox switch and reactivate the enzyme. A deficiency in MPST activity is implicated in a rare inheritable condition known as MCDU (mercaptolactate-cysteine disulfiduria).

NAA10 is a member of the acetyltransferase family. NAA10 interacts with NAA15, HIF-1 and with the ribosome. In its binding to HIF-1, NAA10 functions as a protein acetyltransferase by regulating its stability. In various cell lines, NAA10 is downregulated in response to hypoxia. NAA10 is expressed during the course of the development of the brain.

7-methylguanosine phosphate-specific 5'-nucleotidase (NT5C3B) includes transferase activity and nucleotide binding. Among NT5C3B’s related super-pathways are adenosine nucleotides degradation II and Pyrimidine metabolism. NT5C3B hydrolyzes 7-methylguanosine monophosphate (m(7)GMP) to 7-methylguanosine and inorganic phosphate. The specific activity for m(7)GMP guards cells against undesired retrieval of m(7)GMP and its incorporation into nucleic acids. In addition, NT5C3B has weak activity for CMP.

O-Sialoglycoprotein Endopeptidase, also known as OSGEP is a member of the KAE1 / TsaD family. OSGEP is essential for the formation of threonylcarbamoyl group on adenosine at position 37 (t6A37) in tRNAs which read codons beginning with adenine. OSGEP take a direct catalytic part in the above reaction, however other proteins of the complex are required to fulfill this activity.

PCMT1 enzyme catalyses the methyl esterification of L-isoaspartyl and D-aspartyl residues in peptides and proteins that result from spontaneous decomposition of normal L-aspartyl and L-asparaginyl residues. PCMT1 is involved in the repair and/or degradation of damaged proteins.

General control of amino acid synthesis protein 5 like 2 (KAT2A) is a member of the GCN5 family. KAT2A functions as a histone acetyltransferase (HAT) to promote transcriptional activation. Acetylation of histones gives a specific tag for epigenetic transcription activation. KAT2A interacts with Ku70, TAF9, transcription initiation protein SPT3 homolog, TADA2L, Ku80 and DDB1.

Gankyrin (proteasome 26S subunit) is a multicatalytic proteinase oncoprotein commonly overexpressed in most hepatocellular carcinomas. Proteasomes are found throughout eukaryotic cells at a high concentrations and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. Gankyrin interacts with S6 ATPase of the 19S regulatory particle of the 26S proteasome. Gankyrin is involved in theregulation of the phosphorylation of the retinoblastoma protein by CDK4, and to enhance the ubiquitinylation of p53 by MDM2. Gankyrin consists of 7 ankyrin repeats and is structurally similar to I kappa Bs. Gankyrin acts as a regulatory subunit of the 26s proteasome which is involved in the atp-dependent degradation of ubiquitinated proteins. Gankyrin is involved in progression of esophageal squamous cell carcinoma. gankyrin plays an oncogenic role especially in early stages of human epatocarcinogenesis. Gankyrin binds to NF-kappaB and suppresses its activity at the transcription level by modulating acetylation through SIRT1. Structural comparison between Gankyrin & p16(INK4A) identified numerous residues of gankyrin that are potentially important for CDK4 binding.

AnsA is a cytoplasmic asparaginase from E.coli involved in intracellular asparagine utilization. E.coli has 2 L-asparaginases: the cytoplasmic type I form (ansA) and the periplasmic type II form (ansB). AnsA (Type L asparaginase) is constitutively expressed and is obligatory for the growth of the bacteria on asparagine as the sole nitrogen source.

Uridine diphosphate glucose pyrophosphatase (NUDT14), is a part of the nudix hydrolase family. NUDT14 is a cytoplasmic protein which contains one nudix hydrolase domain and acts as the sugar donor in numerous glycosylation reactions, including those involved in the production of glycogen. NUDT14 hydrolyzes ADP-ribose into ribose 5-phosphate and AMP, and UDP-glucose to glucose 1-phosphate and UMP. NUDT14 is a homodimer which binds magnesium as a cofactor and is encoded by a gene located on human chromosome 14.

Adenylate kinases play a role in regulating the adenine nucleotide composition within a cell by catalyzing the reversible transfer of phosphate groups among adenine nucleotides. There are 3 types of adenylate kinase isozymes, AK1, AK2, and AK3 in vertebrates. Expression of these isozymes are tissue-specific and developmentally regulated. AK2 is localized in the mitochondrial intermembrane space and is involved in apoptosis. AK2 is mutated in individuals with reticular dysgenesis.

The AsnRS enzyme is a member of the ligases family, specifically those forming carbon-oxygen bonds in aminoacyl-tRNA and related compounds. An asparagine-tRNA ligase is an enzyme which catalyzes the chemical reaction: ATP + L-asparagine + tRNAAsn AMP + diphosphate + L-asparaginyl-tRNAAsn. The three substrates of the AsnRS enzyme are ATP, L-asparagine, and tRNA(Asn), whereas its three products are AMP, diphosphate, and L-asparaginyl-tRNA(Asn).

Asparagine synthetase (ASNS) is a cytoplasmic enzyme that turns aspartate toasparagine and functions mostly in mammalian organs. ASNS is responsible for cell growthand its mRNA content is associated with changes in the cell cycle. ASNS may also play a role as a biomarker for ovarian cancer.

PAPPA is a large zinc binding protein, which acts as a metalloprotease and specifically cleaves IGFBP-4 and IGFBP-5, resulting in release of bound IGF. PAPP-A can also act as a regulator of IGF bioactivity in a number of biological systems, including the human ovary and cardiovascular systems. It was shown that PAPP A levels are elevated in patients with unstable angina or acute myocardial infarction. Furthermore, PAPPA is believed to be involved in local proliferative processes such as wound healing and bone remodeling. Moreover, PAPP-A is produced in high concentrations during pregnancy and is released into the maternal circulation. In placenta, PAPP A is expressed in X cells in septa and anchoring villi, and in syncytiotrophoblasts in the chorionic villi.
Lower levels of PAPPA are found in an array of other tissues including kidney, myometrium, endometrium, ovaries, breast, prostate, bone marrow, colon, fibroblasts and osteoblasts. PAPP-A is present in serum and placenta during pregnancy; with levels increasing throughout pregnancy. Low levels of PAPP A are associated with a number of foetal chromosomal abnormalities, as well as pre-eclampsia and stillbirth.
PAPPA levels may be a potentially highly specific marker for heart disease.
PAPP-A proteolytic activity is inhibited by targeting substrate exosite binding.

Mannoside Acetylglucosaminyltransferase 2 (MGAT2) is a golgi enzyme catalyzing an vital step in the conversion of oligomannose to complex N-glycans. MGAT2 enzyme has the characteristic glycosyltransferase domains: a short N-terminal cytoplasmic domain, a hydrophobic non-cleavable signal-anchor domain, and a C-terminal catalytic domain. MGAT2 gene mutations may lead to carbohydrate-deficient glycoprotein syndrome, type II.

UPP1 catalyzes the reversible phosphorylytic cleavage of uridine and deoxyuridine to uracil and ribose- or deoxyribose-1-phosphate which are used as carbon and energy sources or in the release of pyrimidine bases for nucleotide synthesis. UPP1 is part of the family of glycosyltransferases, specifically the pentosyltransferases. Pyrimidine nucleoside phosphorylases add ribose or deoxyribose to pyrimidine bases to form nucleosides that can be incorporated into RNA or DNA.