The key function of a conserved and modified rRNA residue in the ribosomal response to the nascent peptide.

ABSTRACT: The ribosome is able to monitor the structure of the nascent peptide and can stall in response to specific peptide sequences. Such programmed stalling is used for the regulation of gene expression. The molecular mechanisms of the nascent-peptide recognition and ribosome stalling are unknown. We identified the conserved and posttranscriptionally modified 23S rRNA nucleotide m(2)A2503 located at the entrance of the ribosome exit tunnel as a key component of the ribosomal response mechanism. A2503 mutations abolish nascent-peptide-dependent stalling at the leader cistrons of several inducible antibiotic resistance genes and at the secM regulatory gene. Remarkably, lack of the C2 methylation of A2503 significantly function induction of expression of the ermC gene, indicating that the functiona

SUBMITTER: Vazquez-Laslop N 

PROVIDER: S-EPMC2944061 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature