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Structural basis for mRNA and tRNA positioning on the ribosome.

ABSTRACT: Protein synthesis requires the accurate positioning of mRNA and tRNA in the peptidyl-tRNA site of the ribosome. Here we describe x-ray crystal structures of the intact bacterial ribosome from Escherichia coli in a complex with mRNA and the anticodon stem-loop of P-site tRNA. At 3.5-A resolution, these structures reveal rearrangements in the intact ribosome that clamp P-site tRNA and mRNA on the small ribosomal subunit. Binding of the anticodon stem-loop of P-site tRNA to the ribosome is sufficient to lock the head of the small ribosomal subunit in a single conformation, thereby preventing movement of mRNA and tRNA before mRNA decoding.

SUBMITTER: Berk V

PROVIDER: S-EPMC1635088 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

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Structural basis for mRNA and tRNA positioning on the ribosome.

Berk Veysel V Zhang Wen W Pai Raj D RD Cate Jamie H D JH

Proceedings of the National Academy of Sciences of the United States of America 20061012 43

Protein synthesis requires the accurate positioning of mRNA and tRNA in the peptidyl-tRNA site of the ribosome. Here we describe x-ray crystal structures of the intact bacterial ribosome from Escherichia coli in a complex with mRNA and the anticodon stem-loop of P-site tRNA. At 3.5-A resolution, these structures reveal rearrangements in the intact ribosome that clamp P-site tRNA and mRNA on the small ribosomal subunit. Binding of the anticodon stem-loop of P-site tRNA to the ribosome is sufficie ...[more]

PMID: 17038497

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