Noise in gene expression determines cell fate in Bacillus subtilis.
Random cell-to-cell variations in gene expression within an isogenic population can lead to transitions between alternative states of gene expression. Little is known about how these variations (noise) in natural systems affect such transitions. In Bacillus subtilis, noise in ComK, the protein that regulates competence for DNA uptake, is thought to cause cells to transition to the competent state in which genes encoding DNA uptake proteins are expressed. We demonstrate that noise in comK expression selects cells for competence and that experimental reduction of this noise decreases the number of competent cells. We also show that transitions are limited temporally by a reduction in comK transcription. These results illustrate how such stochastic transitions are regulated in a natural system and suggest that noise characteristics are subject to evolutionary forces.
Maamar
Hédia
H
Public Health Research Institute Center, New Jersey Medical School, 225 Warren Street, Newark, NJ 07103, USA.
Raj
Arjun
A
Dubnau
David
D
D001412:Bacillus subtilis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D005075:Biological Evolution; D025461:Feedback, Physiological; D015964:Gene Expression Regulation, Bacterial; D011401:Promoter Regions, Genetic; D014176:Protein Biosynthesis; D020871:RNA Stability; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013269:Stochastic Processes; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism*; D014169:Transformation, Bacterial
D001426:Bacterial Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; D014157:Transcription Factors; C087449:comK protein, Bacillus subtilis