Asymmetric division triggers cell-specific gene expression through coupled capture and stabilization of a phosphatase
- Harvard University, United States
Abstract
Formation of a division septum near a randomly chosen pole during sporulation in B. subtilis creates unequal sized daughter cells with dissimilar programs of gene expression. An unanswered question is how polar septation activates a transcription factor (σF) selectively in the small cell. We present evidence that the upstream regulator of σF, the phosphatase SpoIIE, is compartmentalized in the small cell by transfer from the polar septum to the adjacent cell pole where SpoIIE is protected from proteolysis and activated. Polar recognition, protection from proteolysis, and stimulation of phosphatase activity are linked to oligomerization of SpoIIE. This mechanism for initiating cell-specific gene expression is independent of additional sporulation proteins; vegetative cells engineered to divide near a pole sequester SpoIIE and activate σF in small cells. Thus, a simple model explains how SpoIIE responds to a stochastically-generated cue to activate σF at the right time and in the right place.
Article and author information
Author details
Reviewing Editor
- Michael Laub, Massachusetts Institute of Technology, United States
Version history
- Received: April 16, 2015
- Accepted: October 13, 2015
- Accepted Manuscript published: October 14, 2015 (version 1)
- Version of Record published: December 17, 2015 (version 2)
- Version of Record updated: April 25, 2017 (version 3)
Copyright
© 2015, Bradshaw & Losick
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Asymmetric division triggers cell-specific gene expression through coupled capture and stabilization of a phosphatase
eLife 4:e08145.
https://doi.org/10.7554/eLife.08145
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