title: Cholera toxin affects nuclear ADP-ribosylation in GH1 cells.
abstract: Incubation of GH1 cells with cholera toxin for 24 h inhibits [32P]ADP-ribose incorporation into histones and non-histone nuclear proteins by more than 50%. The toxin produces a generalized decrease of incorporation into all protein acceptors and into the poly(ADP-ribosyl)ated components excised from chromatin after micrococcal nuclease digestion. The cellular levels of NAD were also decreased (40 to 80%) after treatment with cholera toxin. The inhibition of poly(ADP-ribosyl)ation is preceded by an increase of [32P]ADP-ribose incorporation, since incubation with the toxin for 3 h caused an increase instead of a decrease of incorporation. Incubation with dibutyryl cyclic AMP for 24 h also inhibited nuclear poly(ADP-ribosyl)ation, thus showing that the effect of cholera toxin might be mediated by cyclic AMP.
authors.affiliation: Instituto de Investigaciones Biomedicas. CSIC. Fctad de Medicina. Universidad Autonoma, Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Aranda
authors.forename: A
authors.initials: A
authors.lastname: Pascual
authors.forename: R
authors.initials: R
authors.lastname: Copp
authors.forename: H
authors.initials: H
authors.lastname: Samuels
mesh_terms: D036002:ADP Ribose Transferases; D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D003994:Bucladesine / Q000494:pharmacology; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D002772:Cholera Toxin / Q000494:pharmacology*; D002843:Chromatin / Q000378:metabolism; D000242:Cyclic AMP / Q000096:biosynthesis; D006657:Histones / Q000378:metabolism; D008836:Micrococcal Nuclease / Q000378:metabolism; D008970:Molecular Weight; D009243:NAD / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism; D010430:Pentosyltransferases / Q000378:metabolism; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases
chemical_list: D002843:Chromatin; D006657:Histones; D009687:Nuclear Proteins; D009243:NAD; D000246:Adenosine Diphosphate Ribose; D003994:Bucladesine; D002772:Cholera Toxin; D000242:Cyclic AMP; D036002:ADP Ribose Transferases; D010430:Pentosyltransferases; D011065:Poly(ADP-ribose) Polymerases; D008836:Micrococcal Nuclease