The ribosome derives the energy to translocate and unwind mRNA from EF-G binding.

ABSTRACT: The GTPase EF-G catalyzes translocation of mRNA and tRNAs relative to the ribosome and helps maintain the reading frame during protein synthesis. Which events directly require EF-G-mediated GTP hydrolysis during translocation are still debated. Using high-resolution optical tweezers endowed with single-molecule fluorescence detection, we simultaneously monitored binding of fluorescently-labeled EF-G to ribosomes and either mRNA unwinding or mRNA translocation relative to the body domain of the small ribosomal subunit. Using EF-G mutants and GTP analogs, we find that neither mRNA unwinding nor translocation require GTP hydrolysis and that these are independent events that may or may not temporally coincide. We propose that "tight binding" of EF-G to the ribosome triggers mRNA unwinding and

SUBMITTER: Amiri H 

PROVIDER: S-EPMC12775393 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature