title: Endogenous ADP-ribosylation of elongation factor 2 in polyribosome fraction of rabbit reticulocytes.
abstract: Several polypeptides of about 120, 96, 85, 60 and 38 kDa are shown to be radiolabeled during incubation of the mono- and polyribosome fraction of rabbit reticulocytes with [32P]NAD. Among them is a polypeptide coinciding with elongation factor 2 (EF-2) in its electrophoretic mobility in SDS-polyacrylamide gel. The addition of pure EF-2 to the polyribosome fraction results in an increase of the radioactive label in this polypeptide band. From this it is concluded that both endogenous and added EF-2 is ADP-ribosylated by an enzyme associated with polyribosomes. A possibility of regulation of protein synthesis through endogenous ADP-ribosylation in vivo is considered.
mesh_terms: D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D000818:Animals; D009243:NAD / Q000378:metabolism; D009702:Nucleoside Diphosphate Sugars / Q000378:metabolism*; D009713:Nucleotidyltransferases / Q000378:metabolism; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases; D011132:Polyribosomes / Q000378:metabolism*; D011817:Rabbits; D012156:Reticulocytes / Q000378:metabolism*
chemical_list: D009702:Nucleoside Diphosphate Sugars; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors; D009243:NAD; D000246:Adenosine Diphosphate Ribose; D011065:Poly(ADP-ribose) Polymerases; D009713:Nucleotidyltransferases