title: Poly(ADP-ribosyl)ation of p53 during apoptosis in human osteosarcoma cells.
abstract: Spontaneous apoptosis in human osteosarcoma cells was observed to be associated with a marked increase in the intracellular abundance of p53. Immunoprecipitation and immunoblot analysis revealed that, together with a variety of other nuclear proteins, p53 undergoes extensive poly(ADP-ribosyl)ation early during the apoptotic program in these cells. Subsequent degradation of poly(ADP-ribose) (PAR), attached to p53 presumably by PAR glycohydrolase, the only reported enzyme to degrade PAR, was apparent concomitant with the onset of proteolytic processing and activation of caspase-3, caspase-3-mediated cleavage of poly(ADP-ribose) polymerase (PARP), and internucleosomal DNA fragmentation during the later stages of cell death. The decrease in PAR covalently bound to p53 also coincided with the marked induction of expression of the p53-responsive genes bax and Fas. These results suggest that poly(ADP-ribosyl)ation may play a role in the regulation of p53 function and implies a regulatory role for PARP and/or PAR early in apoptosis.
authors.affiliation: Department of Biochemistry and Molecular Biology, Georgetown University School of Medicine, Washington, DC 20007, USA. smulson@bc.georgetown.edu
authors.forename: C M
authors.initials: CM
authors.lastname: Simbulan-Rosenthal
authors.forename: D S
authors.initials: DS
authors.lastname: Rosenthal
authors.forename: R
authors.initials: R
authors.lastname: Luo
authors.forename: M E
authors.initials: ME
authors.lastname: Smulson
mesh_terms: D017209:Apoptosis / Q000502:physiology*; D001859:Bone Neoplasms / Q000378:metabolism / Q000473:pathology*; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D053938:DNA Fragmentation; D004789:Enzyme Activation; D015972:Gene Expression Regulation, Neoplastic; D006026:Glycoside Hydrolases / Q000378:metabolism; D006801:Humans; D009363:Neoplasm Proteins / Q000378:metabolism*; D012516:Osteosarcoma / Q000378:metabolism / Q000473:pathology*; D011064:Poly Adenosine Diphosphate Ribose / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D051028:bcl-2-Associated X Protein; D019014:fas Receptor / Q000096:biosynthesis / Q000235:genetics
chemical_list: C494826:BAX protein, human; D009363:Neoplasm Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; D019014:fas Receptor; D011064:Poly Adenosine Diphosphate Ribose; D011065:Poly(ADP-ribose) Polymerases; D006026:Glycoside Hydrolases; C022407:poly ADP-ribose glycohydrolase; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases