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Phospholipase A2 (PLA2) catalyzes the hydrolysis of the sn-2 position of membrane glycerophospholipids to liberate arachidonic acid (AA), a precursor of eicosanoids including prostaglandins and leukotrienes. The same reaction also produces lysophosholipids, which represent another class of lipid mediators.
The secretory PLA2 (sPLA2) family, in which 10 isozymes have been identified, consists of low molecular weight, Ca2+-requiring secretory enzymes that have been implicated in a number of biological processes, such as modification of eicosanoid generation, inflammation, and host defense.
This enzyme has been proposed to hydrolyze phosphatidylcholine (PC) in lipoproteins to liberate lyso-PC and free fatty acids in the arterial wall, thereby facilitating the accumulation of bioactive lipids and modified lipoproteins in atherosclerotic foci.
In mice, sPLA2 expression significantly influences HDL particle size and composition and demonstrate that an induction of sPLA2 is required for the decrease in plasma HDL cholesterol in response to inflammatory stimuli. Instillation of bacteria into the bronchi was associated with surfactant degradation and a decrease in large:small ratio of surfactant aggregates in rats.

GSTO1 belongs to the theta class glutathione S-transferase-like (GSTTL) protein family. GSTO1 is expressed in a broad array of human tissues and exhibits glutathione-dependent thiol transferase and dehydroascorbate reductase activities as well as catalyzing the reduction of monomethylarsonate which is an intermediate in the pathway of arsenic biotransformation. Furthermore, GSTO1 shields from oxidative stress which is a risk factor for Alzheimer disease, vascular dementia and stroke. GSTO1 is abundant in alveolar macrophages and airway secretions, with the levels reduced in chronic obstructive pulmonary disease patients. In mouse, the GSTO1 protein acts as a small stress response protein, probably involved in cellular redox homeostasis.

UBE2D3 enzymes are human homologs of the yeast UBC4/5 family and play many important regulatory roles in inflammation and cancer. UbcH5a mediates the degradation of a myriad of short-lived regulatory proteins (such as p53 in the presence of E6/E6-AP or MDM2, c-Fos, I?B?, p105) and abnormal proteins. UBE2D3 has 88% and 89% sequence identity with UbcH5a and UbcH5b respectively.

The 14-3-3 family of proteins plays a key regulatory role in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are at least seven isoforms that have been identified in mammals. The 14-3-3gamma, a subtype of the 14-3-3 family of proteins, was thought to be brain and neuron-specific. It has been shown to interact with RAF1 and protein kinase C, proteins involved in various signal transduction pathways.

AKR1C1 transfers progesterone to its inactive state or in other words catalyzes the reaction of 20-alpha-hydroxy progesterone (20-alpha-OHP). In the liver and intestine. AKR1C1 transfers bile and monitors the intrahepatic bile acid concentration though it has a low bile-binding ability. AKR1C1 participates in myelin formation. AKR1C1 is part of the aldo/keto reductase superfamily, which has over 40 known enzymes which catalyze the conversion of aldehydes and ketones to their corresponding alcohols by utilizing NADH and/or NADPH as cofactors thus display overlapping but distinct substrate specificity.

Enteropeptidase or enterokinase is an enzymeinvolved in human digestion. It is produced by cells in the duodenum wall, and is secreted from duodenum's glands, the crypts of Lieberk?hn, whenever ingested food enters the duodenum from the stomach. Enteropeptidase has the critical job of turning trypsinogen(a zymogen) to trypsin, indirectly activating a number of pancreaticdigestive enzymes.
Enteropeptidase is a serine proteaseenzyme(EC3.4.21.9). Enteropeptidase is a part of the Chymotrypsin-clan of serine proteases, and is structurally similar to these proteins.

PSMA6 belongs to the peptidase T1A family, which is a 20S core alpha subunit. The proteasome is a multicatalytic proteinase complex with an extremely organized ring-shaped 20S core structure. The core structure consists of 4 rings of 28 non-identical subunits; 2 rings consist of 7 alpha subunits and 2 rings consist of 7 beta subunits. PSMA6 is spread all over eukaryotic cells in large quantities and cleave peptides in an ATP/ubiquitin-dependent procedure in a non-lysosomal pathway.

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.

Tyrosyl-DNA Phosphodiesterase 2 (TDP2), belongs to the CCR4/nocturin family of divalent cation-dependent phosphodiesterases.TDP2 associates with CD40, tumor necrosis factor (TNF) receptor-75 and TNF receptor associated factors (TRAFs), and inhibits nuclear factor-kappa-B activation. TDP2 is characterized by similar sequence and structure as APE1 endonuclease, which participates in DNA repair and the activation of transcription factors.

Peroxiredoxin 6 (PRDX6) belongs to the thiol-specific antioxidant protein family. PRDX6 is a bifunctional enzyme with 2 distinct active sites. PRDX6 is involved in redox regulation of the cell and can reduce Hydrogen peroxide and short chain organic, fatty acid, and phospholipid hydroperoxides. PRDX6 may have a role in the regulation of phospholipid turnover as well as in protection against oxidative injury. Furthermore, PRDX6 eases the oxidative stress and TGF-beta-induced abnormalities of human trabecular meshwork cells. In addition, PRDX6 is necessary for blood vessel integrity in injured skin.
At acidic pH, PRDX6 binds to reduced phospholipids, however at cytosolic pH PRDX6 binds only to phospholipids that are oxidized which is compatible with the role for PRDX6 in the repair of peroxidized cell membranes. Hydrogen peroxide-mediated hyperoxidation of PRDX6 induces cell cycle arrest at the G2/M transition via up-regulation of iPLA2 activity. Overexpression of PRDX6 is linked to oligodendroglioma.

CKB is a cytoplasmic enzyme that takes part in energy homeostasis. CKB enzyme reversibly catalyzes the transfer of phosphate among ATP and various phosphogens such as creatine phosphate. CKB functions as a homodimer in the brain as well as in different tissues, and as a heterodimer with a similar muscle isozyme in heart. Creatine kinases supply the energy of phosphate hydrolysis essential to drive the normal role of many cellular systems including muscle, tumor and cancer 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.

UbcH12 is functional in in vitro NEDDylation reactions. It has been shown to form a thioester linkage with NEDD8 in the presence of the NEDD8 activating enzyme complex Uba3/APP-BP1. APP-BP1 binds to the amyloid precursor protein (APP) carboxy terminal domain and is important in conjunction with Uba3 and UbcH12 in driving cells through the S to M checkpoint. It was demonstrated to be the E2 responsible for the NEDDylation of the Cul-1 component of the SCF (?-TRCP) complex which is important as the E3-ligase in the ubiquitinylation of I?B?. NEDDylation of Cul-1 is essential for conjugation and processing of NF-?B p105 by SCF (?-TRCP) following phosphorylation of the complex. A dominant negative form of UbcH12, previously demonstrated to sequester NEDD8 and inhibit its conjugation, inhibits both conjugation and processing of p105, which is alleviated by wild-type UbcH12.

Ubiquitin Conjugating Enzyme E2Q2 (UBE2Q2) is a protein coding gene which receives ubiquitin from the E1 complex and catalyzes its covalent attachment to various proteins. UBE2Q2 which is a part of the ubiquitin-conjugating enzyme family is detected in hypopharyngeal head and neck squamous cell carcinoma and in tumor masses.

Trypsin inhibitor SPINK1 is secreted from pancreatic acinar cells into pancreatic fluid. SPINK1 has a role in inhibition of trypsin-catalyzed premature initiation of zymogens in the pancreas and the pancreatic duct. Alterations in SPINK1 gene are the cause for tropical calcific and pancreatitis hereditary pancreatitis.

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.

PPME1 catalyzes the demethylation and inactivation of protein phosphatase (PP2A), a multimeric phosphoserine/ threonine protein phosphatase related to growth inhibition and cell cycle arrest. PPME1 can demethylate PP2A catalytic subunit in vitro and okadaic acid treatment can inhibit this reaction. It is conserved from yeast to human and holds a motif found in lipases having a catalytic triad activated serine as their active site nucleophile.

SEPSECS catalyzes the last step of sec synthesis by way of converting O-phosphoseryl-tRNA(sec) to selenocysteinyl-tRNA(sec) using selenophosphate as the selenium donor. Furthermore, SEPSECS protein is considered a specific marker of autoimmune hepatitis.

Sulfotransferase 1A2 (SULT1A2) belongs to the sulfotransferase family. Sulfotransferase enzymes catalyze the sulfate conjugation of many hormones, neurotransmitters, drugs, and xenobiotic compounds. SULT1A2 mediates the metabolic activation of carcinogenic N-hydroxyarylamines to DNA binding products and might thus participate as a modulating factor of cancer risk.

AK1 is a small ubiquitous enzyme which is essential for maintenance and cell growth. It is involved in the regulation of adenine nucleotide composition within a cell by catalyzing the reversible transfer of the terminal phosphate group between ATP and AMP. The AK1 protein is found in the cytosol of skeletal muscle, brain and erythrocytes. Defects in the AK1 gene are the cause of a form of hemolytic anemia.

CD44 is a cell-surface glycoprotein that plays a role in cell-cell interactions, cell adhesion and migration. CD44 is a receptor for hyaluronic acid and also interacts with other ligands, such as osteopontin, collagens, and matrix metalloproteinases. CD44 participates in a wide variety of cellular functions such as lymphocyte activation, recirculation and homing, hematopoiesis, and tumor metastasis. CD44 and CD49d are putative activity markers and CD44 a potential novel therapeutic target in multiple sclerosis. Increased CD44 antigen is associated with relapses in non-small cell lung cancers.

PPP1R1A is an inhibitor of protein-phosphatase 1. IPP-1 protein plays important in hormonal control of glycogen metabolism. Hormones that elevate intracellular cAMP elevate IPP-1 activity. PPP1R1A activation caused cAMP to control over proteins that are not directly phosphorylated by PKA following a rise in intracellular calcium, IPP-1 is inactivated by calcineurin (PP2B). Multiple domains in IPP-1 target cellular PP1 complexes. PPP1R1A is a cellular regulator of eIF2 alpha phosphorylation.

Matrix metalloproteinase-14 (MMP14), is a membrane-anchored zinc-binding endopeptidase which is expressed at the leading edge of different invasive carcinomas and also promotes tumor cell invasion through degradation of the extracellular matrix. MMP14 takes a vital part in extracellular matrix, ECM, remodeling by having the capability to degrade type I collagen, activate pro-MMP-2 and process cell adhesion molecules for instance CD44 and integrin alpha V. MMP14 is a key enzyme in many physiological as well as pathological processes for example angiogenesis & tumor invasion.