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Protein tyrosine phosphatase mitochondrial 1 (PTPMT1) is a broadly expressed PTP membrane protein with high expression levels in pancreatic beta cells. The PTPMT1 protein is completely restricted to the matrix face of the inner membrane of the mitochondrion. PTPMT1 is responsible for dephosphorylating mitochondrial proteins and thus has a major role in the production of ATP. PTPMT1 exhibits a specific preference for the lipid signaling molecule phosphatidylinositol 5-phosphate as substrate.

HNRNPC is a member of the subfamily of ubiquitously expressed heterogeneous nuclear ribonucleoproteins (hnRNPs) which are related to pre mRNAs in the nucleus and effect pre mRNA processing and other aspects of mRNA metabolism and transport. Although all of the hnRNPs are present in the nucleus, several hnRNPs travel between the nucleus and the cytoplasm. The hnRNP proteins have specific nucleic acid binding properties.

SORBS3 is an SH3 domain-containing adaptor protein. The existence of SH3 domains in the SORBS3 protein have a role in its capability to attach to other cytoplasmic molecules and contribute to cystoskeletal organization, cell adhesion and migration, signaling, and gene expression. Various transcript variants encoding different isoforms are known for this gene.

S100A8 is a part of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a broad range of cells, and participate in the regulation of cellular processes such as cell cycle progression and differentiation. S100A8 plays a role in the inhibition of casein kinase and as a cytokine. S100A8 altered expression is related with cystic fibrosis disease. S100A8 is a calcium-binding protein that has antimicrobial activity against bacteria and fungi.S100A8 is crucial for resistance towards invasion by pathogenic bacteria. S100A8 up-regulates transcription of genes that are under the control of NF-kappa-B. S100A8 plays a role in the development of endotoxic shock in response to bacterial lipopolysaccharide. S100A8 endorses tubulin polymerization and promotes phagocyte migration and infiltration of granulocytes at sites of wounding. S100A8 takes part as a pro-inflammatory mediator in acute and chronic inflammation and up-regulates the release of IL8 and cell-surface expression of ICAM1.

SERPINB5 (Maspin) is a tumor suppressor protein of the serine proteinase inhibitor family. Maspin plays a vital role in embryonic development through critical functions in cell adhesion. In addition, Maspin is present in normal breast and prostatic epithelial cells although down regulated in the particular carcinomas. SERPINB5 impedes the growth, invasion, and metastatic properties of mammary tumors as well as the invasive ability of pancreatic ductal adenocarcinoma cells. SERPINB5 being a breast tumor suppressor gene is a significant marker of the disease progression in breast neoplasms. Furthermore, high expression of maspin is linked to squamous cell carcinoma in non-small-cell lung cancer. Moreover, maspin expression has been directly linked with the biological aggressiveness of ovarian carcinoma. Maspin exhibits no serine protease inhibitory activity since it does not undergo the stressed to relaxed conformational transition typical of active serpins.

GPN-loop GTPase 1 (GPN1) is a member of the GPN-loop GTPase family. GPN1 is a guanosine triphosphatase enzyme which has a role in DNA repair and may function in activation of transcription. Small GTPases, which share a biochemical mechanism, act as binary molecular switches and function in the cell is nucleocytoplasmic transport of both proteins and RNA. In addition, GPN1 establishs an interface between the RNA polymerase II enzyme and chaperone/scaffolding protein, proposing that it is essential to connect RNA polymerase II to regulators of protein complex formation. GPN1 may also be involved in nuclear localization of XPA.

PPIH is a part of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and increase protein folding. PPIH enzyme is a precise factor of the complex that comprises pre-mRNA processing factors PRPF3, PRPF4, and PRPF18, as well as U4/U5/U6 tri-snRNP. PPIH possess PPIase activity and acts as a protein chaperone that mediates the interactions between different proteins inside the spliceosome.

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.

GSTT1 belongs to a superfamily of proteins which catalyze the conjugation of reduced glutathione to a variety of electrophilic and hydrophobic compounds. GSTT1 is one of the GSTs’ four main classes: alpha, mu, pi and theta (which includes GSTT1 and GSTT2). GSTT1 is involved in activation and detoxification reactions and catalyzes the conjugation of industrial chemicals, such as epoxybutane, ethylene oxides, halomethane with glutathione. GSTT1 is found in erythrocytes, at low levels in the liver as well as in Clara and ciliated cells at the alveolar/bronchiolar junction in the lung.
The GSTT1 gene is deficient in 38% of the population. The GSTTI enzyme deficiency might influence the individual risk for development of acquired aplastic anemia and acute myeloid leukemia. The presence or absence of the GSTT1 gene is concurrent with GSST1+ (the conjugator) and GSTT1- (the non-conjugator) phenotypes correspondingly. The GSTT1+ phenotype is able to catalyze the glutathione conjugation of dichloromethane. GSTT1-null genotypes are seen as having a higher risk of developing leukoplakia. Germline genetic polymorphism in GSTT1 is linked to breast cancer.

Malate dehydrogenase (EC1.1.1.37) is an enzyme in the citric acid cycle that catalyzes the conversion of malate into oxaloacetate (using NAD+) and vice versa (this is a reversible reaction). Malate dehydrogenase is not to be confused with malic enzyme, which catalyzes the conversion of pyruvate using NADPH.
Malate dehydrogenase is also involved in gluconeogenesis, the synthesis of glucose from smaller molecules. Pyruvate in the mitochondria is acted upon by pyruvate carboxylase to form oxaloacetate, a citric acid cycle intermediate. In order to get the oxaloacetate out of the mitochondria, malate dehydrogenase reduces it to malate, and it then traverses the inner mitochondrial membrane. Once in the cytosol, the malate is oxidized back to oxaloacetate by cytosolic malate dehydrogenase. Finally, phosphoenol-pyruvate carboxy kinase (PEPCK) converts oxaloacetate to phosphoenol pyruvate.

Citrate synthase also known as CS is a Krebs tricarboxylic acid cycle enzyme which catalyzes the synthesis of citrate from oxaloacetate and acetyl coenzyme A. CS is present in almost all cells capable of oxidative metabolism. CS is nuclear encoded and transported into the mitochondrial matrix, where the mature form is found. The diseases related to CS are: critical illness polyneuropathy and mitochondrial cardiomyopathy.

GLRX2 is a multifunctional enzyme with glutathione-dependent oxidoreductase, glutathione peroxidase and glutathione S-transferase (GST) activity. The disulfide bond functions as an electron carrier in the glutathione-dependent synthesis of deoxyribonucleotides by the enzyme ribonucleotide reductase. In addition, it is also involved in reducing cytosolic protein- and non-protein-disulfides in a coupled system with glutathione reductase. Required for resistance to reactive oxygen species (ROS) by directly reducing hydroperoxides and for the detoxification of ROS-mediated damage. Glutaredoxins are a family of glutathione-dependent hydrogen donors that participate in a variety of cellular redox reactions.

Human Phosphoserine phosphatase (hPSP) is an important enzyme in the phosphorylated pathway of serine biosynthesis, which contributes a major portion of the endogenous L-serine. Similar to known L-3-phosphoserine phosphatases, it catalyzed the Mg2+-dependent hydrolysis of L-phosphoserine and an exchange reaction between L-serine and L-phosphoserine. Recently, its complex structures reveal that the open-closed environmental change of the active site, generated -helical bundle domain, is important to substrate by local rearrangement of the recognition and hydrolysis.

Luciferase is a general term for the class of oxidative enzymes used in bioluminescence and is distinct from a photoprotein. Luciferase catalyzes a bioluminescent reaction which involves the substrate luciferin as well as Mg2+ and ATP, produces green light with a wavelength of 562 nm. Luciferase from firefly is broadly used as a reporter for studying gene regulation and function, and for pharmaceutical screening.

NQO2 is a flavoprotein that catalyzes the 2-electron reduction of diverse quinones, redox dyes, and the vitamin K menadione. NQO2 mainly uses dihydronicotinamide riboside (NRH) as the electron donor. NQO2 catalyzes the metabolic detoxification of quinones and their derivatives to hydroquinones. This detoxification process protects cells against quinone-induced oxidative stress, cytotoxicity and mutagenicity.

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.

UGDH is part of the UDP-glucose/GDP-mannose dehydrogenase family and is a widely expressed enzyme localized in the liver. UGDH transfers UDP-glucose to UDP-glucuronate and thus takes part in the biosynthesis of glycosaminoglycans such as hyaluronan, chondroitin sulfate, and heparan sulfate. These glycosylated products are ordinary molecules of the extracellular matrix and participate in signal transduction, cell migration, and cancer growth and metastasis.

Protein Tyrosine Phosphatase Receptor Type N (PTPRN) is a catalytically inactive protein and a major target of autoimmune response in diabetes mellitus. The long C-terminal intracellular tail covers the majority of autoantibody epitopes. PTPRN is expressed in neural, neuroendocrine and pancreatic islet cells.

Glutathione S-transferase A4 (GSTA4) is a member of the GST superfamily. The GSTA4 enzyme is involved in cellular defense against toxic, carcinogenic, and pharmacologically active electrophilic compounds. GSTA4 shows an especially high activity with reactive carbonyl compounds such as alk-2-enals. GSTA4 is extremely effective in catalyzing the conjugate addition of reduced glutathione to 4-hydroxynonenal, which is an important product of peroxidative degradation of arachidonic acid and a frequently used biomarker for oxidative damage in tissue. The GSTA4 enzyme is expressed at a high level in the brain, placenta, and skeletal muscle and much lower in the lung and liver.

Cytosolic and membrane-bound types of GST are encoded by 2 different supergene families. There are 8 classes of the soluble cytoplasmic mammalian GST: alpha, kappa, mu, omega, pi, sigma, theta and zeta. The mu class of enzymes functions in the detoxification of electrophilic compounds, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress, by conjugation with glutathione. The genes encoding the mu class of enzymes are arranged in a gene cluster on chromosome 1p13.3 and aare highly polymorphic. These genetic differences can change an individual's resistance to carcinogens and toxins as well as affect the toxicity and efficacy of certain drugs. Null mutations of this class mu gene have been linked with the rise in a number of cancers.

GLRX1 has a glutathione-disulfide oxidoreductase activity in the presence of nadph and glutathione reductase. reduces low molecular weight disulfides and proteins. Glutaredoxin is a glutathione (GSH)-dependent hydrogen donor for ribonucleotide reductase and also catalyzes glutathione-disulfide oxidoreduction reactions in the presence of NADPH and glutathione reductase. GLRX1 is multifunctional enzyme with glutathione-dependent oxidoreductase, glutathione peroxidase and glutathione S-transferase (GST) activity. The disulfide bond functions as an electron carrier in the glutathione-dependent synthesis of deoxyribonucleotides by the enzyme ribonucleotide reductase. In addition, it is also involved in reducing cytosolic protein- and non-protein-disulfides in a coupled system with glutathione reductase. Required for resistance to reactive oxygen species (ROS) by directly reducing hydroperoxides and for the detoxification of ROS-mediated damage.

PCYT2 is a member of the cytidylyltransferase family. PCYT2 is an enzyme which catalyzes the formation of CDP-MEA from CTP and phospho MEA in the Kennedy pathway of phospholipid synthesis. PCYT2 has the strongest expression in the liver, heart, and skeletal muscle.

PNMT is an enzyme located in the adrenal medulla and it catalyzes the final step of the catecholamine biosynthesis pathway. PNMT has beta-carboline 2N-methyltransferase activity. PNMT takes part in regulating epinephrine production. Glucocorticoid receptors form multimers of PNMT independent of the DNA binding domain. PNMT expression is regulated late in mouse gestation by AP2-alpha and glucocorticoids.