EF-G catalyzes tRNA translocation by disrupting interactions between decoding center and codon-anticodon duplex.



Liu, Guangqiao, Song, Guangtao, Zhang, Danyang, Zhang, Dejiu, Li, Zhikai, Lyu, Zhixin, Dong, Jianshu, Achenbach, John ORCID: 0000-0001-8161-4335, Gong, Weimin, Zhao, Xin Sheng
et al (show 2 more authors) (2014) EF-G catalyzes tRNA translocation by disrupting interactions between decoding center and codon-anticodon duplex. Nature structural & molecular biology, 21 (9). 817 - 824.

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Abstract

During translation, elongation factor G (EF-G) catalyzes the translocation of tRNA2-mRNA inside the ribosome. Translocation is coupled to a cycle of conformational rearrangements of the ribosomal machinery, and how EF-G initiates translocation remains unresolved. Here we performed systematic mutagenesis of Escherichia coli EF-G and analyzed inhibitory single-site mutants of EF-G that preserved pretranslocation (Pre)-state ribosomes with tRNAs in A/P and P/E sites (Pre-EF-G). Our results suggest that the interactions between the decoding center and the codon-anticodon duplex constitute the barrier for translocation. Catalysis of translocation by EF-G involves the factor's highly conserved loops I and II at the tip of domain IV, which disrupt the hydrogen bonds between the decoding center and the duplex to release the latter, hence inducing subsequent translocation events, namely 30S head swiveling and tRNA2-mRNA movement on the 30S subunit.

Item Type: Article
Uncontrolled Keywords: Escherichia coli, Peptide Elongation Factor G, Escherichia coli Proteins, Codon, RNA, Transfer, Anticodon, Sequence Alignment, Mutagenesis, Amino Acid Sequence, Protein Conformation, RNA Transport, Models, Molecular, Molecular Sequence Data
Subjects: Q Science > Q Science (General)
Q Science > QP Physiology
Q Science > QR Microbiology
Depositing User: Symplectic Admin
Date Deposited: 26 Nov 2015 16:10
Last Modified: 14 Nov 2019 17:12
DOI: 10.1038/nsmb.2869
URI: http://livrepository.liverpool.ac.uk/id/eprint/2039300
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