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Insights into translational termination from the structure of RF2 bound to the ribosome.

ABSTRACT: The termination of protein synthesis occurs through the specific recognition of a stop codon in the A site of the ribosome by a release factor (RF), which then catalyzes the hydrolysis of the nascent protein chain from the P-site transfer RNA. Here we present, at a resolution of 3.5 angstroms, the crystal structure of RF2 in complex with its cognate UGA stop codon in the 70S ribosome. The structure provides insight into how RF2 specifically recognizes the stop codon; it also suggests a model for the role of a universally conserved GGQ motif in the catalysis of peptide release.

SUBMITTER: Weixlbaumer A

PROVIDER: S-EPMC2642913 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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Insights into translational termination from the structure of RF2 bound to the ribosome.

Weixlbaumer Albert A Jin Hong H Neubauer Cajetan C Voorhees Rebecca M RM Petry Sabine S Kelley Ann C AC Ramakrishnan Venki V

Science (New York, N.Y.) 20081101 5903

The termination of protein synthesis occurs through the specific recognition of a stop codon in the A site of the ribosome by a release factor (RF), which then catalyzes the hydrolysis of the nascent protein chain from the P-site transfer RNA. Here we present, at a resolution of 3.5 angstroms, the crystal structure of RF2 in complex with its cognate UGA stop codon in the 70S ribosome. The structure provides insight into how RF2 specifically recognizes the stop codon; it also suggests a model for ...[more]

PMID: 18988853

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