RNA present in post-ribosomal supernatants makes ribosomes susceptible to inactivation by gelonin and alpha-sarcin.
The remarkable resistance of isolated ribosomes to gelonin is overcome by cofactors present in post-ribosomal supernatants. In rat liver post-ribosomal supernatant RNA is the cofactor responsible of the sensitization of ribosomes. Isolated RNA, which consists mostly of deacylated tRNA, accounts for less than 10 per cent of the activity of the original supernatant. The activity of the supernatant is completely destroyed by micrococcal nuclease and RNAase A and also by proteinase K, suggesting that some protein enhances the effect of RNA. RNA has a role also in the sensitization of ribosomes to alpha-sarcin, an RNAase which inactivates ribosomes by hydrolyzing a single phosphodiester bond in the same region of 28S rRNA which is the target of the N-glycosidase activity of gelonin.
Brigotti
M
M
Dipartimento di Patologia sperimentale dell'Università di Bologna, Italy.
Carnicelli
D
D
Sperti
S
S
Montanaro
L
L
D000818:Animals; D001156:Artemia; D001345:Autoradiography; D003600:Cytosol / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D019286:Endopeptidase K; D004722:Endoribonucleases; D005656:Fungal Proteins / Q000494:pharmacology*; D008099:Liver / Q000378:metabolism; D008970:Molecular Weight; D010761:Phosphorus Radioisotopes; D010940:Plant Proteins / Q000494:pharmacology*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology*; D012313:RNA / Q000302:isolation & purification / Q000378:metabolism*; D012335:RNA, Ribosomal / Q000302:isolation & purification / Q000378:metabolism; D012339:RNA, Ribosomal, 28S / Q000378:metabolism*; D012343:RNA, Transfer / Q000302:isolation & purification / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D012156:Reticulocytes / Q000378:metabolism; D012259:Ribonuclease, Pancreatic; D054789:Ribosome Inactivating Proteins, Type 1; D012270:Ribosomes / Q000187:drug effects / Q000378:metabolism*; D012697:Serine Endopeptidases
D005656:Fungal Proteins; D010761:Phosphorus Radioisotopes; D010940:Plant Proteins; D011500:Protein Synthesis Inhibitors; D012335:RNA, Ribosomal; D012339:RNA, Ribosomal, 28S; D054789:Ribosome Inactivating Proteins, Type 1; C014801:alpha-sarcin; D012313:RNA; C025674:GEL protein, Gelonium multiflorum; D012343:RNA, Transfer; D004722:Endoribonucleases; D012259:Ribonuclease, Pancreatic; D012697:Serine Endopeptidases; D019286:Endopeptidase K