title: Effects of the active aldehyde group generated by RNA N-glycosidase in the sarcin/ricin domain of rat 28S ribosomal RNA on peptide elongation.
abstract: Effects of the active aldehyde group of ribose C1' at position 4324 of rat 28S rRNA, in the inactivated ribosome generated by RNA N-glycosidases (trichosanthin, A-chain of cinnamomin and ricin), on peptide elongation have been studied. The aldehyde group inhibits the activities of eEF1A-dependent aminoacyl-tRNA binding to the inactivated ribosome and eEF1A-dependent GTPase, but increases eEF2-dependent activity. At a high concentration of RNA N-glycosidase, the generated aldehyde group also inhibits aminoacyl-tRNA binding to the inactivated ribosome in the absence of elongation factor and translocation activity. When the aldehyde group is reduced into a hydroxyl group by sodium borohydride or blocked with an amino acid through nucleophilic addition, the activities of eEF1A-dependent aminoacyl-tRNA binding and eEF1A-dependent GTPase of the inactivated ribosome are partially restored, but the altered activities of eEF2-dependent GTPase, translocation and aminoacyl-tRNA binding in the absence of elongation factor are not normalized. Thus, reduction or blockage of the aldehyde group with sodium borohydride or amino acids might change the conformation of the S/R domain in rat 28S ribosomal RNA to meet the requirement for eEF1A-dependent reactions, but not eEF2-involved reactions.
authors.affiliation: Shanghai Institute of Biochemistry, Chinese Academy of Sciences.
authors.forename: Y Z
authors.initials: YZ
authors.lastname: Xu
authors.forename: W Y
authors.initials: WY
authors.lastname: Liu
mesh_terms: D000447:Aldehydes / Q000378:metabolism* / Q000494:pharmacology*; D020418:Algal Proteins; D000818:Animals; D000970:Antineoplastic Agents / Q000378:metabolism; D001665:Binding Sites; D001692:Biological Transport / Q000187:drug effects; D003603:Cytotoxins / Q000235:genetics; D004722:Endoribonucleases / Q000737:chemistry*; D005656:Fungal Proteins; D020963:GTP Phosphohydrolase-Linked Elongation Factors / Q000494:pharmacology; D020558:GTP Phosphohydrolases / Q000187:drug effects / Q000378:metabolism; D009699:N-Glycosyl Hydrolases / Q000378:metabolism*; D010441:Peptide Chain Elongation, Translational / Q000187:drug effects*; D020648:Peptide Elongation Factor 1 / Q000494:pharmacology; D010445:Peptide Elongation Factors / Q000494:pharmacology; D010649:Phenylalanine; D017434:Protein Structure, Tertiary; D011500:Protein Synthesis Inhibitors / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D012339:RNA, Ribosomal, 28S / Q000378:metabolism* / Q000494:pharmacology*; D012346:RNA, Transfer, Amino Acyl / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D054788:Ribosome Inactivating Proteins; D054790:Ribosome Inactivating Proteins, Type 2; D012276:Ricin / Q000737:chemistry*; D015978:Trichosanthin / Q000378:metabolism
chemical_list: D000447:Aldehydes; D020418:Algal Proteins; D000970:Antineoplastic Agents; D003603:Cytotoxins; D005656:Fungal Proteins; D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors; D011500:Protein Synthesis Inhibitors; D011506:Proteins; D012339:RNA, Ribosomal, 28S; D012346:RNA, Transfer, Amino Acyl; D054790:Ribosome Inactivating Proteins, Type 2; C061930:cinnamomin, Phytophthora cinnamomi; C014801:alpha-sarcin; D010649:Phenylalanine; D015978:Trichosanthin; D012276:Ricin; D004722:Endoribonucleases; D009699:N-Glycosyl Hydrolases; D054788:Ribosome Inactivating Proteins; D020963:GTP Phosphohydrolase-Linked Elongation Factors; D020558:GTP Phosphohydrolases