Distinct uS11/Rps14 interactions with the translation preinitiation complex differentially alter the accuracy of start codon recognition.

ABSTRACT: The eukaryotic 43S pre-initiation complex (PIC), containing methionyl initiator transfer RNA (Met-tRNAiMet) in a ternary complex (TC) with eIF2-GTP, scans the messenger RNA (mRNA) leader for an AUG start codon in favorable "Kozak" context. Recognition of AUG triggers the rearrangement of the PIC from an open scanning conformation to a closed arrested state with more tightly bound Met-tRNAiMet. Cryo-EM reconstructions of yeast PICs suggest remodeling of the interaction between 40S protein uS11/Rps14 with ribosomal RNA (rRNA) and mRNA between open and closed states; however, its importance in start codon recognition was unknown. uS11/Rps14-L137 substitutions disrupting rRNA contacts favored in the open complex increase initiation at suboptimal sites, and L137E stabilizes TC binding to PICs r

SUBMITTER: Gupta N 

PROVIDER: S-EPMC11952957 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature