Chemical probing of the tRNA--ribosome complex.

Details

Serval ID
serval:BIB_8713352B0710
Type
Article: article from journal or magazin.
Collection
Publications
Title
Chemical probing of the tRNA--ribosome complex.
Journal
Proceedings of the National Academy of Sciences of the United States of America
Author(s)
Peattie D.A., Herr W.
ISSN
0027-8424 (Print)
ISSN-L
0027-8424
Publication state
Published
Issued date
1981
Volume
78
Number
4
Pages
2273-2277
Language
english
Abstract
We probed the (Escherichia coli) tRNAPhe--ribosome interaction with the chemical reagents dimethyl sulfate and diethyl pyrocarbonate. This monitored the higher-order structure of the tRNA in this biological complex and identified critical sites in the tRNA molecule involved in binding to the ribosome. The methylation of the N-7 position of guanosine and the N-3 position of cytidine as well as diethyl pyrocarbonate attack on adenosines are sensitive to secondary and tertiary interactions. Here we identify specific bases in E. coli Phe-tRNAPhe affected by the interaction with the ribosome. The 70S ribosome protects the N-3 position of cytidine-74 and 75 in the 3'-terminal C-C-A, suggesting a strong, possibly base pairing, interaction between the ribosome and that universal sequence. The ribosome also induces strong reactivities at the N-7 positions of G-24 and G-46 in the central region of the tRNA molecule near the variable-loop domain as well as less significant reactivities at 11 other guanosines. Two of these, G-10 and G-44, are close to G-24 and G-46 in the center of the molecule; the others (guanosines 1, 5, 6, 18, 19, 63, 65, 69, and 71) are in the coaxial acceptor stem-T stem helix. All of the effects are ribosome induced and occur in the presence or absence of the messenger poly(U). Prior chemical modification of the anticodon bases as well as the two adjacent 3' purines and, less effectively, four purines in the anticodon stem prevent stable poly(U)-directed ribosome binding. Thus, we identify the 3' terminal C-C-A sequence, near the peptidyl transferase site, and the anticodon stem and loop of tRNAPhe as forming critical contacts with the ribosome. Other regions of the molecule become reactive on ribosome binding, but these do not suggest a significant conformational change being more likely due to a change of environment.
Keywords
Alkylating Agents, Binding Sites, Diethyl Pyrocarbonate, Escherichia coli, Mutagens, Nucleic Acid Conformation, Protein Binding, RNA, Bacterial/metabolism, RNA, Transfer, Amino Acyl/metabolism, Ribosomes/metabolism, Ribosomes/ultrastructure, Sulfuric Acid Esters
Pubmed
Web of science
Open Access
Yes
Create date
24/01/2008 15:36
Last modification date
20/08/2019 14:46
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