EMD-1055
Locking and unlocking of ribosomal motions.
EMD-1055
Single-particle9.0 Å
Deposition: 22/09/2003Map released: 06/01/2004
Last modified: 04/12/2013
Sample Organism:
Escherichia coli
Sample: 70S ribosome from E. coli complex 70S-fMet-tRNA-Phe-tRNA-EF-Tu-GDP-kirromycin.
Fitted models: 1qza, 1qzd, 1r2x (Avg. Q-score: 0.06566667)
Deposition Authors: Valle M
,
Zavialov A ,
Li W,
Stagg SM ,
Sengupta J,
Nielsen RC,
Nissen P ,
Hervey SC,
Ehrenberg M,
Frank J
Sample: 70S ribosome from E. coli complex 70S-fMet-tRNA-Phe-tRNA-EF-Tu-GDP-kirromycin.
Fitted models: 1qza, 1qzd, 1r2x (Avg. Q-score: 0.06566667)
Deposition Authors: Valle M
,
Zavialov A ,
Li W,
Stagg SM ,
Sengupta J,
Nielsen RC,
Nissen P ,
Hervey SC,
Ehrenberg M,
Frank J
Incorporation of aminoacyl-tRNA into the ribosome as seen by cryo-electron microscopy.
Valle M ,
Zavialov A ,
Li W,
Stagg SM ,
Sengupta J,
Nielsen RC,
Nissen P ,
Harvey SC,
Ehrenberg M,
Frank J
(2003) Nat. Struct. Mol. Biol. , 10 , 899 - 906
,
Zavialov A ,
Li W,
Stagg SM ,
Sengupta J,
Nielsen RC,
Nissen P ,
Harvey SC,
Ehrenberg M,
Frank J
(2003) Nat. Struct. Mol. Biol. , 10 , 899 - 906
Abstract:
Aminoacyl-tRNAs (aa-tRNAs) are delivered to the ribosome as part of the ternary complex of aa-tRNA, elongation factor Tu (EF-Tu) and GTP. Here, we present a cryo-electron microscopy (cryo-EM) study, at a resolution of approximately 9 A, showing that during the incorporation of the aa-tRNA into the 70S ribosome of Escherichia coli, the flexibility of aa-tRNA allows the initial codon recognition and its accommodation into the ribosomal A site. In addition, a conformational change observed in the GTPase-associated center (GAC) of the ribosomal 50S subunit may provide the mechanism by which the ribosome promotes a relative movement of the aa-tRNA with respect to EF-Tu. This relative rearrangement seems to facilitate codon recognition by the incoming aa-tRNA, and to provide the codon-anticodon recognition-dependent signal for the GTPase activity of EF-Tu. From these new findings we propose a mechanism that can explain the sequence of events during the decoding of mRNA on the ribosome.
Aminoacyl-tRNAs (aa-tRNAs) are delivered to the ribosome as part of the ternary complex of aa-tRNA, elongation factor Tu (EF-Tu) and GTP. Here, we present a cryo-electron microscopy (cryo-EM) study, at a resolution of approximately 9 A, showing that during the incorporation of the aa-tRNA into the 70S ribosome of Escherichia coli, the flexibility of aa-tRNA allows the initial codon recognition and its accommodation into the ribosomal A site. In addition, a conformational change observed in the GTPase-associated center (GAC) of the ribosomal 50S subunit may provide the mechanism by which the ribosome promotes a relative movement of the aa-tRNA with respect to EF-Tu. This relative rearrangement seems to facilitate codon recognition by the incoming aa-tRNA, and to provide the codon-anticodon recognition-dependent signal for the GTPase activity of EF-Tu. From these new findings we propose a mechanism that can explain the sequence of events during the decoding of mRNA on the ribosome.