ADP-ribosylation and gene expression.
Gene expression can be defined as the conversion of information existing in a molecule of DNA into a mature RNA or protein product and each step in the process, which requires the concerted action of several macromolecules for completion, may be perturbed by the post-translational modification of specific proteins with ADP-ribose. The participation of poly(ADP-ribose) in the regulation of transcription initiation was examined using cell-free systems for both ribosomal RNA and ribosomal proteins. The presence or absence of poly(ADP-ribose) polymerase did not influence the transcription process. Similarly, under conditions optimal for poly(ADP-ribose) polymerase activity, no change in transcription was observed. A direct contribution of poly(ADP-ribosyl)ation to gene transcription thus could not be detected. In contrast, the addition of 3-aminobenzamide to quiescent hepatoma cells treated with insulin inhibited the stimulation of rRNA synthesis. The high concentrations necessary for this effect suggest that a mono(ADP-ribosyl)ation event participates in the cellular action of insulin. A role in the signal transduction pathway leading to activation of rRNA gene expression has been proposed.
Zahradka
P
P
Department of Physiology, St. Boniface General Hospital Research Centre, University of Manitoba, Winnipeg, Canada.
Yau
L
L
D036002:ADP Ribose Transferases; D000818:Animals; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D011064:Poly Adenosine Diphosphate Ribose / Q000502:physiology*; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics*; D012335:RNA, Ribosomal / Q000235:genetics; D012269:Ribosomal Proteins / Q000096:biosynthesis; D015398:Signal Transduction / Q000235:genetics
D012335:RNA, Ribosomal; D012269:Ribosomal Proteins; D011064:Poly Adenosine Diphosphate Ribose; D036002:ADP Ribose Transferases; D011065:Poly(ADP-ribose) Polymerases