RRC ID 35456
Author Hizukuri Y, Akiyama Y.
Title PDZ domains of RseP are not essential for sequential cleavage of RseA or stress-induced σ(E) activation in vivo.
Journal Mol. Microbiol.
Abstract The Escherichia coli σ(E) extracytoplasmic stress response monitors and responds to folding stress in the cell envelope. A protease cascade directed at RseA, a membrane-spanning anti-σ that inhibits σ(E) activity, controls this critical signal-transduction system. Stress cues activate DegS to cleave RseA; a second cleavage by RseP releases RseA from the membrane, enabling its rapid degradation. Stress control of proteolysis requires that RseP cleavage is dependent on DegS cleavage. Recent in vitro and structural studies found that RseP cleavage requires binding of RseP PDZ-C to the newly exposed C-terminal residue (Val148) of RseA, generated by DegS cleavage, explaining dependence. We tested this mechanism in vivo. Neither mutation in the putative PDZ ligand-binding regions nor even deletion of entire RseP PDZ domains had significant effects on RseA cleavage in vivo, and the C-terminal residue of DegS-processed RseA also little affected RseA cleavage. Indeed, strains with a chromosomal rseP gene deleted for either PDZ domain and strains with a chromosomal rseA V148 mutation grew normally and exhibited almost normal σ(E) activation in response to stress signals. We conclude that recognition of the cleaved amino acid by the RseP PDZ domain is not essential for sequential cleavage of RseA and σ(E) stress response in vivo.
Volume 86(5)
Pages 1232-45
Published 2012-12
DOI 10.1111/mmi.12053
PMID 23016873
MeSH Culture Media Endopeptidases / chemistry* Endopeptidases / genetics Endopeptidases / metabolism Escherichia coli K12 / genetics Escherichia coli K12 / growth & development Escherichia coli K12 / metabolism Escherichia coli K12 / physiology* Escherichia coli Proteins / chemistry* Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism* Gene Expression Regulation, Bacterial* Heat-Shock Response Membrane Proteins / chemistry* Membrane Proteins / genetics Membrane Proteins / metabolism* Mutation PDZ Domains / genetics PDZ Domains / physiology* Sigma Factor / genetics Sigma Factor / metabolism* Signal Transduction Temperature Transcription Factors / chemistry Transcription Factors / genetics Transcription Factors / metabolism*
IF 3.816
Times Cited 10
Prokaryotes E. coli JW0940-KC JW2203-KC JW0198-KC