Differential regulation of spo0A transcription in Bacillus subtilis: glucose represses promoter switching at the initiation of sporulation.
We have shown by S1 nuclease mapping with in vivo transcripts that the differential expression of a sporulation-regulatory gene, spo0A, is regulated by switching of two discrete promoters during the initiation of sporulation in Bacillus subtilis; vegetative mRNA was transcribed from an upstream promoter (Pv, vegetative promoter), and sporulation-specific mRNA was transcribed from the other promoter (Ps, sporulation-specific promoter) about 150 bp downstream of the Pv promoter. Transcription from the Pv promoter was at a low level and shut off at T0.5. On the other hand, transcription from the Ps promoter was strongly induced at T0.5 and increased until T2.5. In the presence of 2% glucose, Pv-directed transcription was not shut off and was observed even at T1.5, whereas the induction of Ps-directed transcription was completely repressed. A mutant in which the spo0A gene was transcribed only from the Ps promoter could sporulate normally in the presence of 0.1% glucose but could not sporulate at all in the presence of 2% glucose. In a catabolite-resistant sporulation mutant carrying crsA47 (sigA47), a mutation within the gene encoding sigma A, normal promoter switching from Pv to Ps was observed in the presence of 2% glucose.
Chibazakura
T
T
Institute of Applied Microbiology, University of Tokyo, Japan.
Kawamura
F
F
Takahashi
H
H
D001412:Bacillus subtilis / Q000235:genetics / Q000502:physiology*; D001426:Bacterial Proteins / Q000096:biosynthesis*; D001483:Base Sequence; D015139:Blotting, Southern; D002701:Chloramphenicol / Q000494:pharmacology; D002874:Chromosome Mapping; D004305:Dose-Response Relationship, Drug; D004352:Drug Resistance, Microbial / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005947:Glucose / Q000494:pharmacology*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D012808:Sigma Factor / Q000502:physiology; D013171:Spores, Bacterial / Q000187:drug effects; D014157:Transcription Factors; D014158:Transcription, Genetic / Q000235:genetics*
D001426:Bacterial Proteins; D012808:Sigma Factor; C080950:Spo0A protein, Bacillus subtilis; D014157:Transcription Factors; D002701:Chloramphenicol; D005947:Glucose