Expression of the chaplin and rodlin hydrophobic sheath proteins in Streptomyces venezuelae is controlled by σ(BldN) and a cognate anti-sigma factor, RsbN

Mol Microbiol. 2012 Jun;84(6):1033-49. doi: 10.1111/j.1365-2958.2012.08070.x. Epub 2012 May 14.


The chaplin and rodlin proteins together constitute the major components of the hydrophobic sheath that coats the aerial hyphae and spores in Streptomyces, and mutants lacking the chaplins are unable to erect aerial hyphae and differentiate on minimal media. We have gained insight into the developmental regulation of the chaplin (chp) and rodlin (rdl) genes by exploiting a new model species, Streptomyces venezuelae, which sporulates in liquid culture. Using microarrays, the chaplin and rodlin genes were found to be highly induced during submerged sporulation in a bldN-dependent manner. Using σ(BldN) ChIP-chip, we show that this dependence arises because the chaplin and rodlin genes are direct biochemical targets of σ(BldN) . sven3186 (here named rsbN for regulator of sigma BldN), the gene lying immediately downstream of bldN, was also identified as a target of σ(BldN) . Disruption of rsbN causes precocious sporulation and biochemical experiments demonstrate that RsbN functions as a σ(BldN) -specific anti-sigma factor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / biosynthesis*
  • Base Sequence
  • Gene Expression Profiling
  • Gene Expression Regulation, Bacterial*
  • Gene Order
  • Microarray Analysis
  • Models, Biological
  • Molecular Sequence Data
  • Sigma Factor / antagonists & inhibitors*
  • Sigma Factor / metabolism*
  • Streptomyces / genetics*
  • Streptomyces / growth & development
  • Streptomyces / metabolism


  • Bacterial Proteins
  • Sigma Factor