The Rip1 protease of Mycobacterium tuberculosis controls the SigD regulon. Academic Article uri icon

Overview

abstract

  • Regulated intramembrane proteolysis of membrane-embedded substrates by site-2 proteases (S2Ps) is a widespread mechanism of transmembrane signal transduction in bacteria and bacterial pathogens. We previously demonstrated that the Mycobacterium tuberculosis S2P Rip1 is required for full virulence in the mouse model of infection. Rip1 controls transcription in part through proteolysis of three transmembrane anti-sigma factors, anti-SigK, -L, and -M, but there are also Rip1-dependent, SigKLM-independent pathways. To determine the contribution of the sigma factors K, L, and M to the Δrip1 attenuation phenotype, we constructed an M. tuberculosis ΔsigKΔ sigL ΔsigM mutant and found that this strain fails to recapitulate the marked attenuation of Δrip1 in mice. In a search for additional pathways controlled by Rip1, we demonstrated that the SigD regulon is positively regulated by the Rip1 pathway. Rip1 cleavage of transmembrane anti-SigD is required for expression of SigD target genes. In the absence of Rip1, proteolytic maturation of RsdA is impaired. These findings identify RsdA/SigD as a fourth arm of the branched pathway controlled by Rip1 in M. tuberculosis.

publication date

  • May 9, 2014

Research

keywords

  • Bacterial Proteins
  • Gene Expression Regulation, Bacterial
  • Mycobacterium tuberculosis
  • Peptide Hydrolases
  • Regulon

Identity

PubMed Central ID

  • PMC4097585

Scopus Document Identifier

  • 84903390263

Digital Object Identifier (DOI)

  • 10.1128/JB.01537-14

PubMed ID

  • 24816608

Additional Document Info

volume

  • 196

issue

  • 14