Previous Article | Next Article ![]()
Journal of Bacteriology, March 2006, p. 1710-1720, Vol. 188, No. 5
0021-9193/06/$08.00+0 doi:10.1128/JB.188.5.1710-1720.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.
Jolanta Zakrzewska-Czerwi
ska,2 and
Keith F. Chater1
John Innes Centre, Norwich Research Park, Colney, Norwich NR4 7UH, United Kingdom,1
Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, ul. Weigla 12, 53-114 Wroc
aw, Poland2
Received 12 August 2005/ Accepted 20 September 2005
The Streptomyces coelicolor partitioning protein ParB binds to numerous parS sites in the oriC-proximal part of the linear chromosome. ParB binding results in the formation of large complexes, which behave differentially during the complex life cycle (D. Jakimowicz, B. Gust, J. Zakrzewska-Czerwinska, and K. F. Chater, J. Bacteriol. 187:3572-3580, 2005). Here we have analyzed the transcriptional regulation that underpins this developmentally specific behavior. Analysis of promoter mutations showed that the irregularly spaced complexes present in vegetative hyphae are dependent on the constitutive parABp1 promoter, while sporulation-specific induction of the promoter parABp2 is required for the assembly of arrays of ParB complexes in aerial hyphae and thus is necessary for efficient chromosome segregation. Expression from parABp2 depended absolutely on two sporulation regulatory genes, whiA and whiB, and partially on two others, whiH and whiI, all four of which are needed for sporulation septation. Because of this pattern of dependence, we investigated the transcription of these four whi genes in whiA and whiB mutants, revealing significant regulatory interplay between whiA and whiB. A strain in which sporulation septation (but not vegetative septation) was blocked by mutation of a sporulation-specific promoter of ftsZ showed close to wild-type induction of parABp2 and formed fairly regular ParB-enhanced green fluorescent protein foci in aerial hyphae, ruling out strong morphological coupling or checkpoint regulation between septation and DNA partitioning during sporulation. A model for developmental regulation of parABp2 expression is presented.
aw, Poland. Phone: 48(0)713371172, ext. 180. Fax: 48(0)713371382. E-mail: jakimow{at}iitd.pan.wroc.pl.
Present address: Protein'eXpert SA, 15 rue des Martyrs, F-38027 Grenoble, France.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»