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SSU72 is an extremely conserved homologue of yeast Ssu72, a CTD phosphatase and a component of the polyadenylation/termination machinery. SSU72 interacts with TFIIB, Rb and DNAM-1 and operates to catalyze the dephosphorylation of target proteins, and taking part in RNA processing and termination via dephosphorylation of Pol II. SSU72 is found in multiple alternatively spliced isoforms.

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.

Phosphoserine aminotransferase (PSAT1) catalyzes the conversion of 3-phosphohydroxypyruvate into 3-phosphoserine which is dephosphorylated consequently by phosphoserine phosphatase to form L-serine. PSAT1 is probably a phosphoserine aminotransferase, based on similarity to proteins in mouse, rabbit, and Drosophila. PSAT1 is expressed at high levels in the brain, liver, kidney and pancreas, and very weakly expressed in the thymus, prostate, testis and colon. Defects in the PSAT1 gene are the cause of phosphoserine aminotransferase deficiency (PSATD). PSATD is distinguished biochemically by low plasma and cerebrospinal fluid concentrations of serine and glycine and clinically by intractable seizures, acquired microcephaly, hypertonia, and psychomotor retardation.

Erythrocyte acylphosphatase (ACYP1) is a cytosolic enzyme which catalyzes the hydrolysis of the carboxyl-phosphate bond of acylphosphates. There are two acylphophatase isoenzymes: ACYP1 and ACYP2. These isoenzymes share 60% homology and have the same substrate specificity, even though ACYP1 has a higher catalytic activity than ACYP2.

Tyrosyl-DNA phosphodiesterase 1 ( TDP1) is required for repairing stalled topoisomerase I-DNA complexes by catalyzing the hydrolysis of the phosphodiester bond between the tyrosine residue of topoisomerase I and the 3-prime phosphate of DNA. TDP1 also detach glycolate from single-stranded DNA having 3-prime phosphoglycolate, suggesting a role in repair of free-radical mediated DNA double-strand breaks.

Phosphopantothenate-cysteine ligase (PPCS) catalyzes the first step in the biosynthesis of coenzyme A (CoA) from pantothenic acid (vitamin B5), which is a vital universal pathway in prokaryotes and eukaryotes. PPCS, being one of the last enzymes in this pathway, converts phosphopantothenate to phosphopantothenoylcysteine.

Inorganic pyrophosphatase (ppa) is a member of the Ppase family. PPA is an enzyme which catalyzes the conversion of one molecule of pyrophosphate to two phosphate ions. Since this is a highly exergonic reaction, it can therefore be coupled to unfavorable biochemical transformations in order to drive these transformations to completion. The role of the PPA enzyme is a critical one in the lipid metabolism (including lipid synthesis and degradation), calcium absorption and bone formation, DNA synthesis, as well as other biochemical transformations.

Phosphotransacetylase (PTA) is a metabolic enzyme (EC 2.3.1.8) that catalyzes the reversible conversion: acetyl-CoA + Pi ⇄ acetyl-phosphate + CoA. The reversible reaction of acetyl-CoA to acetate node and back, is useful in R&D and biotech assays such as Metabolic engineering, Synthetic biology, Production of biopolymers, Enzymatic synthesis of acetyl-phosphate, bacterial signaling
and Fermentation.  Phosphotransacetylase controls acetate formation and manipulates acetyl-CoA flux thus is widely used in protein expression, metabolic engineering, and synthetic pathways.

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.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1122 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 726 residue extracellular domain and a 353 residue cytoplasmic domain. Two ligands, angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2), which bind TIE-2 with high-affinity have been identified. Ang2 has been reported to act as an antagonist for Ang1. Mice engineered to overexpress Ang2 or to lack Ang1 or Tie-1 display similar angiogenic defects.

Paraoxonase 1 also called Esterase-A is involved in the detoxification of organophosphate insecticides such as parathion. Paraoxonase 1 may also confer protection against coronary artery disease by destroying proinflammatory oxidized lipids present in oxidized low-density lipoproteins (LDLs).

PPP1CA is one of the 3 catalytic subunits of protein phosphatase 1 (PP1). PP1 is a serine/threonine specific protein phosphatase which is involved in the regulation of a variety of cellular processes, such as cell division, glycogen metabolism, muscle contractility, protein synthesis, and HIV-1 viral transcription. Increased PP1 activity is detected in the end stage of heart failure. Studies in both human and mice suggest that PP1 is a significant regulator of cardiac function. Mouse studies also propose that PP1 functions as a suppressor of learning and memory.

DUSP3 belongs to the dual specificity protein phosphatase subfamily which inactivates their target kinases by dephosphorylating both the phosphoserine/threonine and phosphotyrosine residues. DUSP3 negatively regulate members of the mitogen-activated protein kinase superfamily that are related to cellular proliferation and differentiation. DUSP3 is expressed in both breast and ovarian tissues and displays activity both for tyrosine-protein phosphate and serine-protein phosphate, but exhibits a strong preference toward phosphotyrosines, specifically dephosphorylates and inactivates ERK1 and ERK2.

Thymidine phosphorylase precursor (TYMP) is a platelet-derived endothelial cell growth factor that catalyzes the formation of thymine and 2-deoxy-D-ribose-1-phosphate from thymidine and orthophosphate. TYMP is an angiogenic inducer that potently stimulates the growth of endothelial cells and induces chemotaxis. TYMP has a highly restricted target cell specificity acting only on endothelial cells. An increased expression of TYMP is found in a broad array of different solid tumors and inflammatory diseases and is frequently associated with poor prognosis. Mutations in the TYMP gene are linked to mitochondrial neurogastrointestinal encephalomyopathy.

TAF10 is a small subunit of TFIID which is related to a subdivision of TFIID complexes. Studies with human and mammalian cells verified that this subunit is mandatory for transcriptional activation by the estrogen receptor, for progression through the cell cycle, and is essential for several cellular differentiation programs.

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.

Phosphoribosyltransferase domain-containing protein 1 (PRTFDC1) is a member of the purine/pyrimidine phosphoribosyltransferase family. PRTFDC1 has a low, barely measurable phosphoribosyltransferase activity (in vitro). PRTFDC1 can bind GMP, IMP and alpha-D-5-phosphoribosyl 1-pyrophosphate (PRPP). PRTFDC1 is not expected to impact purine metabolism or GMP salvage.

TEN1 is part of a complex that binds to single-stranded DNA and is necessary in order to protect telomeres from DNA degradation (CST complex). The CST complex binds single-stranded DNA with high affinity in a sequence-independent mode, while isolated subunits bind DNA with low affinity by themselves. Further to telomere protection, the CST complex has most likely a more general part in DNA metabolism at non-telomeric sites.

PPM1G is part of the PP2C family of Ser/Thr protein phosphatases which are known to be negative regulators of cell stress response pathways. PPM1G is accountable for the dephosphorylation of Pre-mRNA splicing factors, an important factor for the formation of functional spliceosome. PPM1G regulates cell cycle progression. PPM1G mediates histone dephosphorylation/exchange in response to DNA damage or checkpoint recovery in higher eukaryotes. The degradation of p21/WAF1 induced by PPM1G is mediated in a proteasome-dependent manner. Protein phosphatase 1G regulates assembly and function of the beta-catenin degradation complex.

PI3Ka plays a specific role in apoptosis in human colon cancer cells. Injection of neutralizing antibodies specific to PI3Ka into adenocarcinoma cells induced apoptosis, a response that was reverted by treating cells with caspase inhibitor. It was also shown that PI3Ka mediated phosphorylation of the p85a adapter reduces the lipid kinase activity of the heterodimer and this gives hints for PI3K-dependent signaling events not requiring production of 3’-phosphorylated phosphoinositides.
PI3Ka is a key regulator of the initiation of keratinocyte differentiation. A decrease in PI3Ka activity results in a loss of keratinocyte adhesion to the extracellular membrane and the initiation of early phase differentiation.

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.

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.

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.