View source for Translations:Bacillus subtilis/12/en

===Sporulation===
{{main|Sporulation in Bacillus subtilis}}
{{further|Sporulation}}
{{excerpt|Sporulation in Bacillus subtilis|Commitment to sporulation}}Once ''B. subtilis'' commits to sporulation, the [[sigma factor]] sigma F is secreted. This factor promotes sporulation. A sporulation septum is formed and a chromosome is slowly moved into the forespore. When a third of one chromosome copy is in the forespore and the remaining two thirds is in the mother cell, the chromosome fragment in the forespore contains the locus for sigma F, which begins to be expressed in the forespore. In order to prevent sigma F expression in the mother cell, an anti-sigma factor, which is encoded by spoIIAB, is expressed. Any residual anti-sigma factor in the forespore (which would otherwise interfere with sporulation) is inhibited by an anti-anti-sigma factor, which is encoded by spoIIAA. SpoIIAA is located near the locus for the sigma factor, so it is consistently expressed in the forespore. Since the spoIIAB locus is not located near the sigma F and spoIIAA loci, it is expressed only in the mother cell and therefore repress sporulation in that cell, allowing sporulation to continue in the forespore. Residual spoIIAA in the mother cell represses spoIIAB, but spoIIAB is constantly replaced so it continues to inhibit sporulation. When the full chromosome localizes to the forespore, spoIIAB can repress sigma F. Therefore, the genetic asymmetry of the ''B. subtilis'' chromosome and expression of sigma F, spoIIAB and spoIIAA dictate spore formation in ''B. subtilis.'' 
[[File:B._subtilis_sporulation_reg.png|thumb|Regulation of sporulation in B. subtilis]]
{{excerpt|Sporulation in Bacillus subtilis|Nature of regulation|hat=no}}