title: Structure and Function of the Stressosome Signalling Hub.
abstract: The stressosome is a multi-protein signal integration and transduction hub found in a wide range of bacterial species. The role that the stressosome plays in regulating the transcription of genes involved in the general stress response has been studied most extensively in the Gram-positive model organism Bacillus subtilis. The stressosome receives and relays the signal(s) that initiate a complex phosphorylation-dependent partner switching cascade, resulting in the activation of the alternative sigma factor σB. This sigma factor controls transcription of more than 150 genes involved in the general stress response. X-ray crystal structures of individual components of the stressosome and single-particle cryo-EM reconstructions of stressosome complexes, coupled with biochemical and single cell analyses, have permitted a detailed understanding of the dynamic signalling behaviour that arises from this multi-protein complex. Furthermore, bioinformatics analyses indicate that genetic modules encoding key stressosome proteins are found in a wide range of bacterial species, indicating an evolutionary advantage afforded by stressosome complexes. Interestingly, the genetic modules are associated with a variety of signalling modules encoding secondary messenger regulation systems, as well as classical two-component signal transduction systems, suggesting a diversification in function. In this chapter we review the current research into stressosome systems and discuss the functional implications of the unique structure of these signalling complexes.
authors.affiliation: Division of Microbial Physiology and Molecular Biology, University of Greifswald, Greifswald, 17487, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Pané-Farré
authors.affiliation: Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, St. Paul, MN, 55108, USA.
authors.forename: Maureen B
authors.initials: MB
authors.lastname: Quin
authors.affiliation: Institute for Cell and Molecular Biosciences, Faculty of Medical Sciences, University of Newcastle, Newcastle upon Tyne, NE2 4HH, UK.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Lewis
authors.affiliation: School of Biology, Newcastle University, Devonshire Building, Newcastle upon Tyne, NE1 7RU, UK. jon.marles-wright1@ncl.ac.uk.
authors.forename: Jon
authors.initials: J
authors.lastname: Marles-Wright
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics* / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D010766:Phosphorylation; D012808:Sigma Factor / Q000819:agonists / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D001426:Bacterial Proteins; D012808:Sigma Factor
keywords: Bacillus subtilis; Kinase; Phosphorylation; RsbR; RsbS; SigmaB; Stressosome; YtvA