Bacillus subtilis cells may opt to forgo normal cell division and instead form spores if subjected to certain environmental stimuli, for example nutrient deficiency or extreme temperature. The gene regulation net-work governing sporulation initiation accordingly incorporates a variety of signals and is of significant complexity. The present model (Bulletin of Mathematical Biology (2011) 73:181–211) includes four of these signals: nutrient levels, DNA damage, the products of the competence genes, and cell population size. An interesting prediction derived from the model is that PhrA, which is secreted from the cell and subsequently re-imported can act simultaneously as a quorum-sensing signal and as a timing mechanism, delaying sporulation when the cell has damaged DNA, possibly thereby allowing the cell time to repair its DNA before forming a spore.
Simulation link at JWS Online: http://jjj.mib.ac.uk/webMathematica/Examples/run.jsp?modelName=jabbari
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Created: 12th Oct 2011 at 13:56
Last updated: 7th Mar 2012 at 13:43
Last used: 15th Oct 2019 at 07:07