Escherichia coli endoribonuclease RNase E: autoregulation of expression and site-specific cleavage of mRNA.
Mutations in the Escherichia coli rne (ams) gene have a general effect on the rate of mRNA decay in vivo. Using antibodies we have shown that the product of the rne gene is a polypeptide of relative mobility 180 kDa. However, proteolytic fragments as small as 70 kDa, which can arise during purification, also exhibit RNase E activity. In vitro studies demonstrate that the rne gene product, RNase E, is an endoribonuclease that cleaves mRNA at specific sites. RNase E cleaves rne mRNA and autoregulates the expression of the rne gene. In addition we demonstrate RNase E-dependent endonucleolytic cleavage of ompA mRNA, at a site known to be rate-determining for degradation and reported to be cleaved by RNase K. Our data are consistent with RNase K being a proteolytic fragment of RNase E.
Mudd
E A
EA
Imperial Cancer Research Fund Laboratories, University of Oxford, John Radcliffe Hospital, UK.
Higgins
C F
CF
D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis / Q000235:genetics; D001483:Base Sequence; D004722:Endoribonucleases / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D012322:RNA Precursors / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional; D011994:Recombinant Proteins / Q000096:biosynthesis; D013379:Substrate Specificity
D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; D012322:RNA Precursors; D011994:Recombinant Proteins; D004722:Endoribonucleases; C065559:ribonuclease K; C022537:ribonuclease E