Eukaryotic elongation factor 2 loses its non-specific affinity for RNA and leaves polyribosomes as a result of ADP-ribosylation.
ADP-ribosylation of rabbit reticulocyte elongation factor 2 (EF-2) catalyzed by the A fragment of diphtheria toxin leads to a loss of its non-specific affinity for RNA. The removal of the ADP-ribose residue from EF-2 in the reverse reaction with nicotinamide restores its affinity for RNA. ADP-ribosylation of EF-2 is accompanied by its dissociation from the complexes with mono- and polyribosomes detected in the rabbit reticulocyte lysate at low ionic strength. The loss of the non-specific affinity of EF-2 for RNA as a result of ADP-ribosylation and, as a consequence, its decompartmentation from polyribosomes is assumed to be a reason for the diphtheria toxin-induced inactivation of the factor in eukaryotic cells.
D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D000818:Animals; D002499:Centrifugation, Density Gradient; D002846:Chromatography, Affinity; D004167:Diphtheria Toxin / Q000494:pharmacology; D004926:Escherichia coli; D009536:Niacinamide / Q000494:pharmacology; D009702:Nucleoside Diphosphate Sugars / Q000378:metabolism*; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors / Q000378:metabolism*; D011132:Polyribosomes / Q000378:metabolism*; D012313:RNA / Q000378:metabolism*; D012329:RNA, Bacterial / Q000378:metabolism; D011817:Rabbits; D012156:Reticulocytes / Q000378:metabolism
D004167:Diphtheria Toxin; D009702:Nucleoside Diphosphate Sugars; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors; D012329:RNA, Bacterial; D000246:Adenosine Diphosphate Ribose; D009536:Niacinamide; D012313:RNA