Expression of the Bacillus subtilis dinR and recA genes after DNA damage and during competence.
The Bacillus subtilis dinR gene product is homologous to the LexA protein of Escherichia coli and regulates the expression of dinR and dinC. Using transcriptional fusions in the dinR and the recA genes, we have investigated the epistatic relationship between these two genes during the SOS response induced either by DNA damage or by competence. The results show that after DNA damage, induction of the expression of both recA and dinR is dependent on the activity of the DinR and RecA proteins. A RecA-dependent activity on DinR is proposed as the initial event in the induction of the SOS network. In contrast, the competence-related induction of dinR and recA appears to involve two distinct mechanisms. While one mechanism corresponds to the classical regulation of the SOS response, the other appears to involve an activating factor. Moreover, this factor is active in cells in which competence is prevented by a mutation in the regulatory gene comA.
Raymond-Denise
A
A
Unité de Pathogénie Microbienne Moléculaire, Institut National de la Santé et de la Recherche Médicale U199, Institut Pasteur, Paris, France.
Guillen
N
N
D001412:Bacillus subtilis / Q000235:genetics*; D001426:Bacterial Proteins / Q000096:biosynthesis*; D004249:DNA Damage / Q000235:genetics*; D004268:DNA-Binding Proteins; D004843:Epistasis, Genetic; D016685:Mitomycin / Q000494:pharmacology; D011003:Ploidies; D011938:Rec A Recombinases / Q000096:biosynthesis*; D011993:Recombinant Fusion Proteins / Q000235:genetics; D012097:Repressor Proteins; D013014:SOS Response, Genetics / Q000235:genetics*; D014158:Transcription, Genetic
D001426:Bacterial Proteins; C061262:ComA protein, Bacteria; D004268:DNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; C071577:dinR protein, Bacillus subtilis; D016685:Mitomycin; D011938:Rec A Recombinases