Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.143 (poly(ADP-ribose) glycohydrolase)
 208 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rat peritoneal macrophages are known to contain a chymotrypsin-like neutral protease associated with a specific inhibitor. By homogenizing the cells in 0.25 M sucrose (pH 8.0) containing 0.5% Triton X-100, both the protease and the inhibitor were found to be localized in the nuclei, particularly in chromatin. The inhibitory factor in chromatin was then separated from the protease by hydroxylapatite gel chromatography in the presence of 2 M NaCl and 5 M urea. The inhibitor fraction obtained was deproteinized by digestion with Pronase and subsequent extraction with phenol; these treatments did not alter the inhibitory potency. The deproteinized inhibitor fraction had a UV absorption ratio, A280/A260, of 0.61, but it was resistant to digestion with various nucleases, including DNase 1, nuclease P1, and snake venom phosphodiesterase. However, when it was incubated with poly(ADP-ribose) glycohydrolase from calf thymus, the inhibitory potency was markedly decreased. An authentic poly(ADP-ribose), with a mean chain length of approximately 30 ADP-ribose units, produced significant inhibition of the neutral protease isolated from macrophage chromatin. No such inhibition was produced by DNA, single-stranded DNA, RNA, polyadenylate, polyuridylate, polycytidylate, or monomeric ADP-ribose.
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PMID:A chromatin-bound neutral protease and its inhibitor in rat peritoneal macrophages. 71 9

The activities of three principal enzymes engaged in the biosynthesis and degradation of poly(adenosine diphosphate-ribose) [poly(ADP-ribose)] were examined in cell nuclei isolated from adenomatous polyps (tubular adenomas of familial polyposis coli, villous adenoma, and tubulovillous adenoma), cancers, and normal mucosa of human colon. The activities of poly(ADP-ribose) synthetase in adenomatous polyps [161 +/- 46 (S.E.) pmol/min/mg DNA] and cancers (114 +/- 32 pmol/min/mg DNA) were, on an average, about 3 and 2 times, respectively, higher than those in normal mucosa (52 +/- 24 pmol/min/mg DNA); the difference was statistically significant (p less than 0.001). The activity of poly(ADP-ribose) glycohydrolase was also significantly high in adenomatous polyps (13.0 +/- 3.4 nmol/min/mg DNA), but not in cancers (10.1 +/- 2.5 nmol/min/mg DNA), compared with normal mucosa (5.2 +/- 1.4 nmol/min/mg DNA) (p less than 0.001). The activity of ADP-ribosyl protein lyase, in contrast, was lower in adenomatous polyps (152 +/- 40 pmol/min/mg DNA) than in normal mucosa (345 +/- 111 pmol/min/mg DNA) and cancers (288 +/- 80 pmol/min/mg DNA) (p less than 0.001). Analyses of reaction products with snake venom phosphodiesterase digestion revealed that poly(ADP-ribose) synthesized in nuclei of normal mucosa, adenomatous polyps, and cancers had the average chain lengths of 2.9, 1.7, and 9.7 ADP-ribose units, respectively. Based upon these values and total amounts of ADP-ribose incorporated, the amount of poly(ADP-ribose) synthesized per mg DNA in 30 min was calculated as 308, 1510, and 106 pmol in the above three types of colon tissues, respectively. These results suggested that a larger amount of monomers and short oligomers of ADP-ribose was synthesized in adenomatous polyps, while a smaller number of longer polymers was produced in cancers as compared with normal mucosa. Immunohistochemical analysis of these tissues using anti-poly(ADP-ribose) antibody supported this view.
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PMID:Aberration of poly(adenosine diphosphate-ribose) metabolism in human colon adenomatous polyps and cancers. 640 58

Poly(ADP-ribose) synthetic activity in isolated nucleoli from rapidly growing mouse ascites tumor cells and ADP-ribosylation of the nucleolar proteins in vitro were studied. The specific activity of the synthesis in the nucleoli was significantly higher than that in the chromatin. The optimum magnesium and NAD+ concentrations, and the effect of RNase treatment on the reaction in the nucleoli were also distinctly different from those in the chromatin. Hydrolysis of the reaction product of the nucleoli with snake venom phosphodiesterase and with calf thymus poly(ADP-ribose) glycohydrolase yielded 5'-AMP and 2'-(5"-phosphoribosyl))5'-AMP, and ADP-ribose, respectively. The average chain length of the polymer formed in the nucleoli was found to be about 4 as a whole, but the distribution was heterogenous, from 1.2 to over 12. Analysis of ADP-ribosylated proteins in the nucleoli by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate revealed that several non-histone proteins with molecular weights of over 100,000 were highly ADP-ribosylated compared with other proteins including histones. This pattern was also different from that of the chromatin. These experimental results demonstrate that the nucleoli are independent from the chromatin as regards poly(ADP-ribose) synthesis in vitro.
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PMID:Poly(ADP-ribose) synthesis in nucleoli and ADP-ribosylation of nucleolar proteins in mouse ascites tumor cells in vitro. 728 63

Poly(ADP-ribose) polymerase (PARP) (EC 2.4.2.30), the only enzyme known to synthesize ADP-ribose polymers from NAD+, is activated in response to DNA strand breaks and functions in the maintenance of genomic integrity. Mice homozygous for a disrupted gene encoding PARP are viable but have severe sensitivity to gamma-radiation and alkylating agents. We demonstrate here that both 3T3 and primary embryo cells derived from PARP-/- mice synthesized ADP-ribose polymers following treatment with the DNA-damaging agent, N-methyl-N'-nitro-N-nitrosoguanidine, despite the fact that no PARP protein was detected in these cells. ADP-ribose polymers isolated from PARP-/- cells were indistinguishable from that of PARP+/+ cells by several criteria. First, they bound to a boronate resin selective for ADP-ribose polymers. Second, treatment of polymers with snake venom phosphodiesterase and alkaline phosphatase yielded ribosyladenosine, a nucleoside diagnostic for the unique ribosyl-ribosyl linkages of ADP-ribose polymers. Third, they were digested by treatment with recombinant poly(ADP-ribose) glycohydrolase, an enzyme highly specific for ADP-ribose polymers. Collectively, these data demonstrate that ADP-ribose polymers are formed in PARP-/- cells in a DNA damage-dependent manner. Because the PARP gene has been disrupted, these results suggest the presence of a previously unreported activity capable of synthesizing ADP-ribose polymers in PARP-/- cells.
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PMID:Poly(ADP-ribose) polymerase null mouse cells synthesize ADP-ribose polymers. 980 57