Decay of mRNA in Escherichia coli: investigation of the fate of specific segments of transcripts.
An assay was developed to investigate the fate of specific segments of beta-lactamase (bla) and ompA gene transcripts in Escherichia coli. DNA probes cloned in bacteriophage M13 were treated with an endonuclease capable of cleaving single-stranded DNA, the fragments produced were annealed with total cellular RNA, and the resulting RNA . DNA hybrids were subjected to S1 nuclease treatment and gel fractionation. By using this assay, direct evidence was obtained for 3'-to-5' directionality in the decay of the long-lived mRNA encoded by the ompA gene, and no preferential stability was observed for translated versus untranslated mRNA segments. In the case of bla mRNA, initial cleavage of the full-length transcript was rate limiting, and no decay intermediates were detected. No difference in degradation rate was seen for bla transcripts having variant 3' or 5' termini.
D001425:Bacterial Outer Membrane Proteins; D001483:Base Sequence; D002874:Chromosome Mapping; D004926:Escherichia coli / Q000235:genetics*; D005786:Gene Expression Regulation; D007700:Kinetics; D008565:Membrane Proteins / Q000235:genetics; D012329:RNA, Bacterial / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D001618:beta-Lactamases / Q000235:genetics
D001425:Bacterial Outer Membrane Proteins; D008565:Membrane Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; D001618:beta-Lactamases