Suppression of a cold-sensitive mutant initiation factor 1 by alterations in the 23S rRNA maturation region
2011 (English)In: The FEBS Journal, ISSN 1742-464X, E-ISSN 1742-4658, Vol. 278, no 10, 1745-1756 p.Article in journal (Refereed) Published
Genetic selection has been used to isolate second-site suppressors of a defective cold-sensitive initiation factor I (IF1) R69L mutant of Escherichia coli. The suppressor mutants specifically map to a single rRNA operon on a plasmid in a strain with all chromosomal rRNA operons deleted. Here, we describe a set of suppressor mutations that are located in the processing stem of precursor 23S rRNA. These mutations interfere with processing of the 23S rRNA termini. A lesion of RNase III also suppresses the cold sensitivity. Our results suggest that the mutant IF1 strain is perturbed at the level of ribosomal subunit association, and the suppressor mutations partially compensate for this defect by disrupting rRNA maturation. These results support the notion that IF1 is an RNA chaperone and that translation initiation is coupled to ribosomal maturation.
Place, publisher, year, edition, pages
2011. Vol. 278, no 10, 1745-1756 p.
Escherichia coli, RNase III, rRNA mutation, rRNA processing, translation
Research subject Molecular Genetics
IdentifiersURN: urn:nbn:se:su:diva-68511DOI: 10.1111/j.1742-4658.2011.08099.xISI: 000290169300014OAI: oai:DiVA.org:su-68511DiVA: diva2:473692