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Trans-translation exposed: understanding the structures and functions of tmRNA-SmpB.

ABSTRACT: Ribosome stalling is a serious issue for cell survival. In bacteria, the primary rescue system is trans-translation, performed by tmRNA and its protein partner small protein B (SmpB). Since its discovery almost 20 years ago, biochemical, genetic, and structural studies have paved the way to a better understanding of how this sophisticated process takes place at the cellular and molecular levels. Here we describe the molecular details of trans-translation, with special mention of recent cryo-electron microscopy and crystal structures that have helped explain how the huge tmRNA-SmpB complex targets and delivers stalled ribosomes without interfering with canonical translation.

SUBMITTER: Giudice E

PROVIDER: S-EPMC3968760 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Trans-translation exposed: understanding the structures and functions of tmRNA-SmpB.

Giudice Emmanuel E Macé Kevin K Gillet Reynald R

Frontiers in microbiology 20140321

Ribosome stalling is a serious issue for cell survival. In bacteria, the primary rescue system is trans-translation, performed by tmRNA and its protein partner small protein B (SmpB). Since its discovery almost 20 years ago, biochemical, genetic, and structural studies have paved the way to a better understanding of how this sophisticated process takes place at the cellular and molecular levels. Here we describe the molecular details of trans-translation, with special mention of recent cryo-elec ...[more]

PMID: 24711807

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