Toggle Main Menu Toggle Search

Open Access padlockePrints

Antirepression as a second mechanism of transcriptional activation by a minor groove binding protein

Lookup NU author(s): Dr Leendert Hamoen

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Abstract

Competence for genetic transformation in the bacterium Bacillus subtilis is a bistable differentiation process governed by the minor groove DNA binding protein ComK. No detectable comK transcription occurs in the absence of an intact comK gene, indicating that ComK has auto-activating properties. ComK auto-stimulation, which is dependent on ComK binding to the comK promoter, is a critical step in competence development, ensuring quick and high-level expression of the late-competence genes. Auto-stimulation is also essential for the bistable expression pattern of competence. Here, we demonstrate that ComK acts as an activator at its own promoter by antagonizing the action of two repressors, Rok and CodY. Importantly, antirepression occurs without preventing binding of the repressing proteins, suggesting that ComK and the repressors might bind at distinct surfaces of the DNA helix. DegU, a DNA binding protein known to increase the affinity of ComK for its own promoter, potentiates the antirepression activity of ComK. We postulate that antirepression is primarily achieved through modulation of DNA topology. Although to our knowledge ComK is the only DNA binding protein shown to act in this novel fashion, other minor groove binding proteins may act similarly. © 2007 The Authors.


Publication metadata

Author(s): Smits WK, Hoa TT, Hamoen LW, Kuipers OP, Dubnau D

Publication type: Article

Publication status: Published

Journal: Molecular Microbiology

Year: 2007

Volume: 64

Issue: 2

Pages: 368-381

ISSN (print): 0950-382X

ISSN (electronic): 1365-2958

Publisher: Wiley-Blackwell Publishing Ltd.

URL: http://dx.doi.org/10.1111/j.1365-2958.2007.05662.x

DOI: 10.1111/j.1365-2958.2007.05662.x

PubMed id: 17493123


Altmetrics

Altmetrics provided by Altmetric


Share