Structural Basis for the Rescue of Stalled Ribosomes: Structure of YaeJ Bound to the Ribosome
In bacteria, the hybrid transfer-messenger RNA (tmRNA) rescues ribosomes stalled on defective messenger RNAs (mRNAs). However, certain gram-negative bacteria have evolved proteins that are capable of rescuing stalled ribosomes in a tmRNA-independent manner. Here, we report a 3.2 angstrom-resolution...
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Published in | Science (American Association for the Advancement of Science) Vol. 335; no. 6074; pp. 1370 - 1372 |
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Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
Washington, DC
American Association for the Advancement of Science
16.03.2012
The American Association for the Advancement of Science |
Subjects | |
Online Access | Get full text |
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Summary: | In bacteria, the hybrid transfer-messenger RNA (tmRNA) rescues ribosomes stalled on defective messenger RNAs (mRNAs). However, certain gram-negative bacteria have evolved proteins that are capable of rescuing stalled ribosomes in a tmRNA-independent manner. Here, we report a 3.2 angstrom-resolution crystal structure of the rescue factor Yae] bound to the Thermus thermophilus 70S ribosome in complex with the initiator tRNAi fMet and a short mRNA. The structure reveals that the C-terminal tail of Yae] functions as a sensor to discriminate between stalled and actively translating ribosomes by binding in the mRNA entry channel downstream of the A site between the head and shoulder of the 30S subunit. This allows the N-terminal globular domain to sample different conformations, so that its conserved GGQ motif is optimally positioned to catalyze the hydrolysis of peptidyl-tRNA. This structure gives insights into the mechanism of Yae] function and provides a basis for understanding how it rescues stalled ribosomes. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 National Institutes of Health (NIH) These authors contributed equally to this work. |
ISSN: | 0036-8075 1095-9203 |
DOI: | 10.1126/science.1217443 |