title: The initiation codon affects ribosome binding and translational efficiency in Escherichia coli of cI mRNA with or without the 5' untranslated leader.
abstract: Translational efficiency of an AUG, CUG, GUG, or UUG initiation codon was measured for the naturally leaderless cI mRNA from bacteriophage lambda. In a cI-lacZ translational fusion, only AUG supported a high level of expression; GUG supported a low level of expression, while UUG and CUG expression was barely above background levels. Addition of an untranslated lac leader and Shine-Dalgarno sequence to cI increased expression but still showed a dependence on an AUG for maximum expression. cI-lacZ mRNA with an AUG initiation codon showed a greater in vitro ribosome binding strength and a higher level of full-length in vivo mRNA, suggesting that the initiation codon is an important determinant of ribosome binding strength and translational efficiency for mRNA with or without the 5' untranslated leader.
authors.affiliation: Department of Microbiology, Miami University, Oxford, Ohio 45056, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: O'Donnell
authors.forename: G R
authors.initials: GR
authors.lastname: Janssen
mesh_terms: D020121:5' Untranslated Regions / Q000235:genetics* / Q000378:metabolism; D018387:Codon, Initiator; D004926:Escherichia coli; D007763:Lac Operon; D010442:Peptide Chain Initiation, Translational; D012329:RNA, Bacterial / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D011993:Recombinant Fusion Proteins; D012270:Ribosomes / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D020121:5' Untranslated Regions; D018387:Codon, Initiator; D012329:RNA, Bacterial; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins