Premium
How the early sporulation sigma factor σ F delays the switch to late development in Bacillus subtilis
Author(s) -
KarmazynCampelli Céline,
Rhayat Lamya,
CarballidoLópez Rut,
Duperrier Sandra,
Frandsen Niels,
Stragier Patrick
Publication year - 2008
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1111/j.1365-2958.2008.06121.x
Subject(s) - sigma factor , bacillus subtilis , sigma , biology , spore , six sigma , transcription factor , transcription (linguistics) , microbiology and biotechnology , gene , genetics , gene expression , promoter , chemistry , physics , bacteria , linguistics , philosophy , quantum mechanics , chromatography , cascade
Summary Sporulation in Bacillus subtilis is a primitive differentiation process involving two cell types, the forespore and the mother cell. Each cell implements two successive transcription programmes controlled by specific sigma factors. We report that activity of σ G , the late forespore sigma factor, is kept in check by Gin, the product of csfB , a gene controlled by σ F , the early forespore sigma factor. Gin abolishes σ G transcriptional activity when σ G is artificially synthesized during growth, but has no effect on σ F . Gin interacts strongly with σ G but not with σ F in a yeast two‐hybrid experiment. The absence of Gin allows σ G to be active during sporulation independently of the mother‐cell development to which it is normally coupled. Premature σ G activity leads to the formation of slow‐germinating spores, and complete deregulation of σ G synthesis is lethal when combined with gin inactivation. Gin allows σ F to delay the switch to the late forespore transcription programme by preventing σ G to take over before the cell has reached a critical stage of development. A similar strategy, following a completely unrelated route, is used by the mother cell.