The DnaA protein is a key factor for the regulation of the timing and synchrony of initiation of bacterial DNA replication. The transcription of the dnaA gene in Escherichia coli is regulated by two promoters, dnaAP1 and dnaAP2. The region between these two promoters contains several DnaA-binding sites that have been shown to play an important role in the negative auto-regulation of dnaA expression. The results obtained in the present study using an in vitro and in vivo quantitative analysis of the effect of mutations to the high-affinity DnaA sites reveal an additional effect of positive autoregulation. We investigated the role of transcription autoregulation in the change of dnaA expression as a function of temperature. While negative auto-regulation is lost at dnaAP1, the effects of both positive and negative autoregulation are maintained at the dnaAP2 promoter upon lowering the growth temperature. These observations can be explained by the results obtained in vitro showing a difference in the temperature-dependence of DnaA–ATP binding to its high- and low-affinity sites, resulting in a decrease in DnaA–ATP oligomerization at lower temperatures. The results of the present study underline the importance of the role for autoregulation of gene expression in the cellular adaptation to different growth temperatures.
Skip Nav Destination
Article navigation
January 2013
-
Cover Image
Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
- PDF Icon PDF LinkEditorial Board
Research Article|
December 14 2012
Temperature-dependence of the DnaA–DNA interaction and its effect on the autoregulation of dnaA expression
Chiara Saggioro;
Chiara Saggioro
1LBPA (Laboratoire de biologie et pharmacologie appliquée), CNRS, ENS Cachan, 94235 Cachan, France
Search for other works by this author on:
Anne Olliver;
Anne Olliver
1LBPA (Laboratoire de biologie et pharmacologie appliquée), CNRS, ENS Cachan, 94235 Cachan, France
Search for other works by this author on:
Bianca Sclavi
Bianca Sclavi
1
1LBPA (Laboratoire de biologie et pharmacologie appliquée), CNRS, ENS Cachan, 94235 Cachan, France
1To whom correspondence should be addressed (email sclavi@lbpa.ens-cachan.fr).
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
May 29 2012
Revision Received:
October 02 2012
Accepted:
October 23 2012
Accepted Manuscript online:
October 23 2012
Online ISSN: 1470-8728
Print ISSN: 0264-6021
© The Authors Journal compilation © 2013 Biochemical Society
2013
Biochem J (2013) 449 (2): 333–341.
Article history
Received:
May 29 2012
Revision Received:
October 02 2012
Accepted:
October 23 2012
Accepted Manuscript online:
October 23 2012
Citation
Chiara Saggioro, Anne Olliver, Bianca Sclavi; Temperature-dependence of the DnaA–DNA interaction and its effect on the autoregulation of dnaA expression. Biochem J 15 January 2013; 449 (2): 333–341. doi: https://doi.org/10.1042/BJ20120876
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.