DETERMINANT ROLE OF ESCHERICHIA-COLI RNASE-III IN THE DECAY OF BOTH SPECIFIC AND HETEROLOGOUS MESSENGER-RNAS

A comparative analysis of mRNA decay was carried out in Escherichia co li using the wild-type and an isogenic RNase III deletion strain. We h ave studied the mRNA degradation from the Escherichia colt gene bolA, the Lactococcus lactis biovar diacetylactis citQRP operon and the Desu lfovibrio vulgaris Hildenborough gene cyc. As seen by a dramatic stabi lization of the specific mRNAs in the mutant strain, RNase III was cru cial for the decay process of these three messages. Since RNase III, u nlike RNase E, is not essential for bacterial viability we think that there is potential for using RNase III mutant strains to modulate gene expression.