The coming of age of the LeuO regulator
Article first published online: 26 JUL 2012
© 2012 Blackwell Publishing Ltd
Volume 85, Issue 6, pages 1026–1028, September 2012
How to Cite
Hernández-Lucas, I. and Calva, E. (2012), The coming of age of the LeuO regulator. Molecular Microbiology, 85: 1026–1028. doi: 10.1111/j.1365-2958.2012.08175.x
- Issue published online: 10 SEP 2012
- Article first published online: 26 JUL 2012
- Accepted manuscript online: 19 JUL 2012 11:44AM EST
- Accepted 14 July, 2012.
LeuO is a quiescent genetic regulator present in many bacteria, which forms part of the H-NS regulon. LeuO in turn has been proposed to activate a subset of genes of the regulon by antagonizing H-NS. In the paper by Dillon et al., binding of LeuO to the S. Typhimurium genome was observed by ChIP-chip to some of the previously described LeuO-regulated genes, upon growth under stress conditions. However, studies at a higher LeuO concentration from a cloned inducible promoter rendered many more binding sites, pointing towards the importance of the abundance of the regulator in the cell, in a given moment. Binding of LeuO was observed not only to intergenic sequences, but in the majority of cases to intragenic sequences, and co-binding was observed with H-NS in many sites and with RNA polymerase to the majority of sites. The authors define a binding motif that allowed the detection of several other LeuO-regulated genes that were not detected by ChIP-chip, which were possibly missed because LeuO binds and bridges distal sites, in those instances. The observations reported open new questions regarding the mode of action for LeuO.