Open AccessBacillus subtilis rapD , a direct target of transcription repression by RghR, negatively regulates srfA expression
Author(s) -
Ogura Mitsuo,
Fujita Yasutaro
Publication year - 2007
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2006.00559.x
Subject(s) - rapd , regulon , bacillus subtilis , biology , psychological repression , genetics , sigma factor , transcription (linguistics) , gene , regulation of gene expression , gene expression , microbiology and biotechnology , promoter , bacteria , population , linguistics , demography , philosophy , sociology , genetic diversity
The Bacillus subtilis genome encodes eleven Rap proteins, which are conserved tetratricopeptide‐containing regulatory proteins. Of those characterized to date, all except RapI negatively regulate response regulators, including Spo0F, ComA and DegU, via protein–protein interactions. RapD has not yet been fully characterized. It was examined whether RapD inhibits the expression of spoIIE , srfA and aprE , which are Spo0F‐, ComA‐ and DegU‐regulated genes, respectively. It was observed that multicopy rapD inhibited srfA expression, which suggests that RapD inhibits ComA. This was reinforced by the fact that multicopy rapD also blocked the expression of rapC and rapF , which belong to the ComA regulon. The expression of rapD was reported to depend on the extracytoplasmic function sigma factor SigX. DNA microarray analysis and gel retardation assays revealed that rapD expression is directly repressed by RghR. Thus, the ComA regulon is regulated by rapD in a SigX‐ and RghR‐dependent manner.