title: In vitro proteolysis of endonucleases in rat liver nuclei extracts.
abstract: DNA endonucleases in rat liver nuclei extracts were examined by SDS-polyacrylamide gel electrophoresis followed by zymogram analysis. Four polypeptides of 120, 54, 31 and 28 kDa, which have DNA endonuclease activity, were shown to occur in the extract isolated in the presence of phenylmethanesulfonyl fluoride (PMSF), a proteinase inhibitor. Isolation without PMSF, as well as storage at -20 degrees C, or autodigestion, resulted in multiplication of active polypeptides in the extracts. Trypsin digestion led to the appearance of an active > 140 kDa polypeptide, indicating the existence of a potential endonuclease precursor in the nuclear extract.
authors.affiliation: Institute of Biological and Medical Chemistry, Russian Academy of Medical Sciences, Moscow.
authors.forename: L G
authors.initials: LG
authors.lastname: Lebedeva
authors.forename: S S
authors.initials: SS
authors.lastname: Alexandrova
authors.forename: I I
authors.initials: II
authors.lastname: Votrin
authors.forename: A G
authors.initials: AG
authors.lastname: Basnakian
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D004706:Endodeoxyribonucleases / Q000302:isolation & purification / Q000378:metabolism*; D010450:Endopeptidases / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008297:Male; D008970:Molecular Weight; D010446:Peptide Fragments / Q000302:isolation & purification; D010664:Phenylmethylsulfonyl Fluoride / Q000494:pharmacology; D051381:Rats; D014357:Trypsin / Q000378:metabolism
chemical_list: D010446:Peptide Fragments; D010664:Phenylmethylsulfonyl Fluoride; D004706:Endodeoxyribonucleases; D010450:Endopeptidases; D014357:Trypsin