Opposite roles of the dmd gene in the control of RNase E and RNase LS activities.
When the dmd gene of bacteriophage T4 is defective, expression of middle genes starts normally but drops abruptly. However, the residual expression of middle genes at late stages continues at a higher rate in cells infected with a dmd mutant than with the wild type. In order to understand the complex effects of the dmd gene, we followed changes in the quantity of mRNA from a middle gene, uvsY. The uvsY mRNA was degraded rapidly by RNase LS at middle stages but stabilized at late stages, suggesting that RNase LS targets middle-gene mRNAs only at middle stages. Furthermore, another RNase targeting middle mRNAs at late stages is also suggested to be inactivated when dmd is mutated. We found that RNase E was involved in the degradation of uvsY mRNA. Judging from the processing of gene-32 mRNA, RNase E activity declines after the beginning of the middle stage when dmd is defective.
Kanesaki
Takuma
T
Department of Biology, Graduate School of Science, Osaka University, Japan.
Hamada
Takahiro
T
Yonesaki
Tetsuro
T
D017122:Bacteriophage T4 / Q000201:enzymology / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics; D004722:Endoribonucleases / Q000378:metabolism*; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics*; D009154:Mutation; D020871:RNA Stability / Q000235:genetics*; D014764:Viral Proteins / Q000096:biosynthesis / Q000235:genetics*
D004268:DNA-Binding Proteins; D008565:Membrane Proteins; C092864:UvsY protein, Enterobacteria phage T4; D014764:Viral Proteins; C060035:gp32 protein, Enterobacteria phage T4; D004722:Endoribonucleases; C022537:ribonuclease E