title: Ribosome dynamics during decoding.
abstract: Elongation factors Tu (EF-Tu) and SelB are translational GTPases that deliver aminoacyl-tRNAs (aa-tRNAs) to the ribosome. In each canonical round of translation elongation, aa-tRNAs, assisted by EF-Tu, decode mRNA codons and insert the respective amino acid into the growing peptide chain. Stop codons usually lead to translation termination; however, in special cases UGA codons are recoded to selenocysteine (Sec) with the help of SelB. Recruitment of EF-Tu and SelB together with their respective aa-tRNAs to the ribosome is a multistep process. In this review, we summarize recent progress in understanding the role of ribosome dynamics in aa-tRNA selection. We describe the path to correct codon recognition by canonical elongator aa-tRNA and Sec-tRNASecand discuss the local and global rearrangements of the ribosome in response to correct and incorrect aa-tRNAs. We present the mechanisms of GTPase activation and GTP hydrolysis of EF-Tu and SelB and summarize what is known about the accommodation of aa-tRNA on the ribosome after its release from the elongation factor. We show how ribosome dynamics ensures high selectivity for the cognate aa-tRNA and suggest that conformational fluctuations, induced fit and kinetic discrimination play major roles in maintaining the speed and fidelity of translation.This article is part of the themed issue 'Perspectives on the ribosome'.
authors.affiliation: Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, Göttingen 37077, Germany rodnina@mpibpc.mpg.de.
authors.forename: Marina V
authors.identifier: 0000-0003-0105-3879
authors.initials: MV
authors.lastname: Rodnina
authors.affiliation: Department of Structural Dynamics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, Göttingen 37077, Germany.
authors.forename: Niels
authors.identifier: 0000-0002-4609-4052
authors.initials: N
authors.lastname: Fischer
authors.affiliation: Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, Göttingen 37077, Germany.
authors.forename: Cristina
authors.initials: C
authors.lastname: Maracci
authors.affiliation: Department of Structural Dynamics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, Göttingen 37077, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Stark
mesh_terms: D001419:Bacteria / Q000378:metabolism; D005057:Eukaryotic Cells / Q000378:metabolism; D010444:Peptide Elongation Factor Tu / Q000378:metabolism; D010445:Peptide Elongation Factors / Q000378:metabolism*; D012345:RNA, Transfer, Amino Acid-Specific / Q000378:metabolism*; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*
chemical_list: D010445:Peptide Elongation Factors; D012345:RNA, Transfer, Amino Acid-Specific; D012346:RNA, Transfer, Amino Acyl; C036928:tRNA, selenocysteine-; D010444:Peptide Elongation Factor Tu
keywords: decoding; recoding; ribosome; tRNA; translation