Functional Analysis of the Heat Shock Regulator HrcA of Chlamydia trachomatis
AUTOR(ES)
Wilson, Adam C.
FONTE
American Society for Microbiology
RESUMO
HrcA is a regulator of bacterial heat shock gene expression that binds to a cis-acting DNA element called CIRCE. It has been proposed that HrcA and CIRCE function as a repressor-operator pair. We have purified recombinant HrcA from the pathogenic bacterium Chlamydia trachomatis and have shown that it is a DNA-binding protein that functions as a negative regulator of transcription. HrcA bound specifically to the CIRCE element in a concentration-dependent manner. HrcA repressed the in vitro transcription of a chlamydial heat shock promoter, and this repression was promoter specific. HrcA-mediated repression appears to be dependent on the topological state of the promoter, as repression on a supercoiled promoter template was greater than that on a linearized template. These results provide direct support for the role of HrcA as a transcriptional repressor in bacteria. This is the first report of the in vitro reconstitution of transcriptional regulation in Chlamydia.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=135440Documentos Relacionados
- Role of HrcA and CIRCE in the Heat Shock Regulatory Network of Bradyrhizobium japonicum
- Dual Control of Helicobacter pylori Heat Shock Gene Transcription by HspR and HrcA
- Functional and Structural Analysis of HrcA Repressor Protein from Caulobacter crescentus
- hrcA, the first gene of the Bacillus subtilis dnaK operon encodes a negative regulator of class I heat shock genes.
- Differential and Independent Roles of a ς32 Homolog (RpoH) and an HrcA Repressor in the Heat Shock Response of Agrobacterium tumefaciens
