A Novel SRP Recognition Sequence in the Homeostatic Control Region of Heat Shock Transcription Factor σ32.
Sci Rep
; 6: 24147, 2016 Apr 07.
Article
in En
| MEDLINE
| ID: mdl-27052372
ABSTRACT
Heat shock response (HSR) generally plays a major role in sustaining protein homeostasis. In Escherichia coli, the activity and amount of the dedicated transcription factor σ(32) transiently increase upon heat shock. The initial induction is followed by chaperone-mediated negative feedback to inactivate and degrade σ(32). Previous work reported that signal recognition particle (SRP)-dependent targeting of σ(32) to the membrane is essential for feedback control, though how SRP recognizes σ(32) remained unknown. Extensive photo- and disulfide cross-linking studies in vivo now reveal that the highly conserved regulatory region of σ(32) that lacks a consecutive hydrophobic stretch interacts with the signal peptide-binding site of Ffh (the protein subunit of SRP). Importantly, the σ(32)-Ffh interaction observed was significantly affected by mutations in this region that compromise the feedback regulation, but not by deleting the DnaK/DnaJ chaperones. Homeostatic regulation of HSR thus requires a novel type of SRP recognition mechanism.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Sigma Factor
/
Regulatory Sequences, Nucleic Acid
/
Signal Recognition Particle
/
Escherichia coli Proteins
/
Heat-Shock Proteins
Type of study:
Prognostic_studies
Language:
En
Journal:
Sci Rep
Year:
2016
Document type:
Article
Affiliation country:
Japan