Comprehensive DNA microarray analysis of Bacillus subtilis two-component regulatory systems

It has recently been shown through DNA microarray analysis of Bacillus subt ilis two-component regulatory systems (DegS-DegU, ComP-ComA, and PhoR-PhoP) that overproduction of a response regulator of the two-component systems i n the background of a deficiency of its cognate sensor kinase affects the r egulation of genes, including its target ones. The genome-wide effect on ge ne expression caused by the overproduction was revealed by DNA microarray a nalysis. In the present work we newly analyzed 24 two-component systems by means of this strategy, leaving out 8 systems to which it was unlikely to b e applicable. This analysis revealed various target gene candidates for the se two-component systems. It is especially notable that interesting interac tions appeared to take place between several two-component systems. Moreove r, the probable functions of some unknown two-component systems were deduce d from the list of their target gene candidates. This work is heuristic but provides valuable information for further study toward a comprehensive und erstanding of the B. subtilis two-component regulatory systems. The DNA mic roarray data obtained in this work are available at the KEGG Expression Dat abase website (http://www.genome.ad.jp/kegg/expression).