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Cryo-EM structure of the E. coli translating ribosome in complex with SRP and its receptor.

ABSTRACT: We report the 'early' conformation of the Escherichia coli signal recognition particle (SRP) and its receptor FtsY bound to the translating ribosome, as determined by cryo-EM. FtsY binds to the tetraloop of the SRP RNA, whereas the NG domains of the SRP protein and FtsY interact weakly in this conformation. Our results suggest that optimal positioning of the SRP RNA tetraloop and the Ffh NG domain leads to FtsY recruitment.

SUBMITTER: Estrozi LF

PROVIDER: S-EPMC3764645 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Cryo-EM structure of the E. coli translating ribosome in complex with SRP and its receptor.

Estrozi Leandro F LF Boehringer Daniel D Shan Shu-Ou SO Ban Nenad N Schaffitzel Christiane C

Nature structural & molecular biology 20101212 1

We report the 'early' conformation of the Escherichia coli signal recognition particle (SRP) and its receptor FtsY bound to the translating ribosome, as determined by cryo-EM. FtsY binds to the tetraloop of the SRP RNA, whereas the NG domains of the SRP protein and FtsY interact weakly in this conformation. Our results suggest that optimal positioning of the SRP RNA tetraloop and the Ffh NG domain leads to FtsY recruitment. ...[more]

PMID: 21151118

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