The Ams (altered mRNA stability) protein and ribonuclease E are encoded by the same structural gene of Escherichia coli.
The in vitro and in vivo analysis of the ribonuclease E-deficient (rne-) and the altered mRNA stability protein-deficient (ams-) strains of Escherichia coli has demonstrated that they carry mutations in the same structural gene. Strains encoding either thermolabile RNase E (rne-3071) or Ams protein (ams-1) are defective in both rRNA processing and mRNA turnover. Immediately after a shift to the nonpermissive temperature, the chemical decay rate of bulk mRNA is slowed 2- to 3-fold, and within 70 min, precursors to 5S rRNA begin to accumulate. In addition, all of the phenotypes associated with either the rne-3071 or the ams-1 alleles were complemented by a recombinant plasmid carrying ams+. When taken together with previous genetic studies, these results suggest that the role of ribonuclease E in mRNA turnover involves endonucleolytic cleavages at the proposed ACAG(A/U)AUUUG consensus sequence.
Babitzke
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P
Department of Genetics, University of Georgia, Athens 30602.
Kushner
S R
SR
D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002872:Chromosome Deletion; D004251:DNA Transposable Elements; D004722:Endoribonucleases / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D005838:Genotype; D007700:Kinetics; D008969:Molecular Sequence Data; D009876:Operon; D012333:RNA, Messenger / Q000378:metabolism
D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D012333:RNA, Messenger; D004722:Endoribonucleases; C022537:ribonuclease E