Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.4.1 (phosphodiesterase)
 18,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The protein responsible for both nucleotide pyrophosphatase (EC 3.6.1.9) and alkaline phosphodiesterase I (EC 3.1.4.1) activities was purified from MOPC 315 plasmacytoma cells. A single SDS/PAGE-purified 115-kDa protein band was used to produce a rabbit polyclonal antiserum. This antibody preparation precipitated alkaline phosphodiesterase I activity, indicating that the SDS/PAGE-purified protein was nucleotide pyrophosphatase/alkaline phosphodiesterase I. When used for Western blot analysis, the antiserum detected a 115-kDa protein as well as a 220-kDa protein band. Multiple overlapping cDNA clones were isolated from a cDNA expression library screened with this anti-nucleotide pyrophosphatase/alkaline phosphodiesterase I antiserum. Sequence analysis indicated that the isolated cDNA clones encoded PC-1, a murine plasma cell differentiation antigen. To confirm the suspected enzymatic identity of PC-1, a recombinant PC-1 fusion protein was expressed in bacteria, purified, and used to produce another rabbit polyclonal antiserum. This antiserum likewise immunoprecipitated alkaline phosphodiesterase I activity and recognized the 115-kDa and 220-kDa proteins in Western blot analyses of cell extracts. Furthermore, expression of nucleotide pyrophosphatase/alkaline phosphodiesterase I corresponded directly with mRNA and protein levels of PC-1 in cells known to express different levels of nucleotide pyrophosphatase/alkaline phosphodiesterase I activity. Finally, steroid induction of enzymatic activity was mirrored by levels of PC-1 mRNA and protein expression. Together, these data indicate that the plasma cell differentiation antigen PC-1 is a membrane-bound enzyme, nucleotide pyrophosphatase/alkaline phosphodiesterase I.
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PMID:Identification of nucleotide pyrophosphatase/alkaline phosphodiesterase I activity associated with the mouse plasma cell differentiation antigen PC-1. 164 27

The effect of glucocorticoid hormones on the protein responsible for both nucleotide pyrophosphatase (EC 3.6.1.9) and alkaline phosphodiesterase I (EC 3.1.4.1) activities was examined in murine MOPC 315 plasmacytoma cells. Incubation of these cells with dexamethasone resulted in parallel increases in pyrophosphatase and phosphodiesterase specific activities. The incorporation of [3H]mannose into N-linked oligosaccharide precursors was also analyzed in cells following hormone modulation. In cells treated for 36 hours or cultured continuously with dexamethasone, the resulting increase in enzyme specific activities was accompanied by a decrease in [3H]mannose incorporation, consistent with the hypothesis that in some cell types, nucleotide pyrophosphatase activity is involved in the regulation of glycoprotein synthesis.
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PMID:Modulation of nucleotide pyrophosphatase in plasmacytoma cells. 185 Feb 50

A bone and cartilage enzyme with both 5'-nucleotide phosphodiesterase I and nucleotide pyrophosphohydrolase (NTPPPH) activity modulates physiologic mineralization and pathologic chondrocalcinosis by generating inorganic pyrophosphate. We hypothesized that, as for alkaline phosphatase, expression of an NTPPPH gene can be shared by cells from bone, cartilage, and liver and by certain leukocytes. Recently, we demonstrated the hepatocyte and murine plasma cell membrane glycoprotein PC-1 to have both 5'-nucleotide phosphodiesterase I and NTPPPH activity. We detected polypeptides cross-reactive with PC-1 in human U20S osteosarcoma cells, articular chondrocytes, homogenized human knee cartilages, human knee synovial fluids, hepatoma cells, and murine plasmacytoma cells. Constitutive low abundance PC-1 mRNA expression was detected in U20S cells and chondrocytes by a nested RNA-PCR assay and by Northern blotting. TGF beta is known to substantially increase NTPPPH activity in primary osteoblast cultures. We demonstrated that TGF beta 1 increased NTPPPH activity and the level of PC-1 mRNA and immunoprecipitable [35S]-methionine-labeled PC-1 polypeptides in U20S cells. The identification of PC-1 as an NTPPPH expressed in cells derived from bone and cartilage may prove useful in furthering the understanding of the role of NTPPPH i n physiologic and pathologic mineralization.
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PMID:Expression of the murine plasma cell nucleotide pyrophosphohydrolase PC-1 is shared by human liver, bone, and cartilage cells. Regulation of PC-1 expression in osteosarcoma cells by transforming growth factor-beta. 804 Mar 11

PC-1 is a membrane glycoprotein, found on the surface of plasma cells and a few types of nonlymphoid cells, which has recently been found to have 5'-nucleotide phosphodiesterase activity. In this paper, we demonstrate the existence of enzymically active water-soluble forms of PC-1 in ascites from plasmacytoma-bearing mice, normal mouse serum, and in supernatants of cultured mouse plasmacytoma cells and mouse L cells transfected with a cDNA encoding the membrane form of PC-1. The water-soluble enzyme activity can be specifically immunoprecipitated by a monoclonal antibody to an allotypic determinant on the membrane form of PC-1, and resides on a slightly smaller polypeptide than membrane PC-1. Biosynthetic studies revealed a single, monomeric, endoglycosidase-H-sensitive membrane PC-1 precursor, which was gradually converted to a disulphide-bonded, endoglycosidase-H-resistant form over a period of about 2 h. Soluble PC-1 was first detectable in the supernatant after about 2 h. A distinct intracellular form of soluble PC-1 was not seen. The soluble form of PC-1 does not appear to arise by proteolytic cleavage from the cell surface, although cleavage inside the cell remains a possibility. When taken together with the structure of the relevant portions of PC-1 gene exons, the data suggest that the most likely site of cleavage is between Pro152 and Ala153.
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PMID:Identification and characterization of a soluble form of the plasma cell membrane glycoprotein PC-1 (5'-nucleotide phosphodiesterase). 822 81