Synergistic regulation of competence development in Bacillus subtilis by two Rap-Phr systems.
The 11 Rap proteins of Bacillus subtilis comprise a conserved family of tetratricopeptide (TPR)-containing regulatory proteins. Their activity is inhibited by specific Phr pentapeptides produced from the product of phr genes through an export-import maturation process. We found that one of the proteins, namely RapF, is involved in the regulation of competence to DNA transformation. The ComA response regulator and transcription factor for initiation of competence development is the target of RapF. Specific binding of RapF to the carboxy-terminal DNA-binding domain of ComA inhibits the response regulator's ability to bind its target DNA promoters. The PhrF C-terminal pentapeptide, QRGMI, inhibits RapF activity. The activity of RapF and PhrF in regulating competence development is analogous to the previously described activity of RapC and PhrC (L. J. Core and M. Perego, Mol. Microbiol. 49:1509-1522, 2003). In fact, the RapF and PhrF pair of proteins acts synergistically with RapC and PhrC in the overall regulation of the ComA transcription factor. Since the transcription of the RapC- and RapF-encoding genes is positively regulated by their own target ComA, an autoregulatory circuit must exist for the competence transcription factor in order to modulate its activity.
Bongiorni
Cristina
C
Division of Cellular Biology, Mail Code MEM-116, Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Ishikawa
Shu
S
Stephenson
Sophie
S
Ogasawara
Naotake
N
Perego
Marta
M
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004255:Deoxyribodipyrimidine Photo-Lyase / Q000235:genetics*; D004950:Esterases / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D012097:Repressor Proteins / Q000235:genetics; D016415:Sequence Alignment; D014169:Transformation, Bacterial / Q000235:genetics*
D001426:Bacterial Proteins; C061262:ComA protein, Bacteria; D004268:DNA-Binding Proteins; D008565:Membrane Proteins; C101115:PhrC protein, Bacillus subtilis; D012097:Repressor Proteins; C070739:comQ protein, Bacillus subtilis; D004950:Esterases; C101114:RapC protein, Bacillus subtilis; D004255:Deoxyribodipyrimidine Photo-Lyase