Regulation of the Bacillus subtilis extracytoplasmic function protein sigma(Y) and its target promoters.
The Bacillus subtilis extracytoplasmic function sigma factor sigma(Y) is of unknown function. We demonstrate that the sigY operon is expressed from an autoregulatory promoter site, P(Y). We selected for transposon-induced mutations that upregulate P(Y) transcription in an attempt to identify genes involved in sigma(Y) regulation. The resulting insertions disrupted yxlC, the gene immediately downstream of sigY. However, the phenotype of the yxlC::Tn10 insertion was due to polarity on the downstream genes of the sigY operon; a nonpolar insertion in yxlC did not lead to derepression of P(Y). Further analyses revealed that both yxlD and yxlE encoded proteins important for the negative regulation of sigma(Y) activity. A comparison of the transcriptomes of wild-type and yxlC::Tn10 mutant strains revealed elevated expression of several operons. However, only one additional gene, ybgB, was unambiguously identified as a direct target for sigma(Y). This was supported by analysis of direct targets for sigma(Y) transcription with whole-genome runoff transcription followed by macroarray analysis.
Cao
Min
M
Department of Microbiology, Cornell University, Ithaca, New York 14853-8101, USA.
Salzberg
Letal
L
Tsai
Ching Sung
CS
Mascher
Thorsten
T
Bonilla
Carla
C
Wang
Tao
T
Ye
Rick W
RW
Márquez-Magaña
Leticia
L
Helmann
John D
JD
D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D003593:Cytoplasm; D004251:DNA Transposable Elements; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D009876:Operon; D011401:Promoter Regions, Genetic / Q000235:genetics*; D020543:Proteome; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D020543:Proteome; D012808:Sigma Factor