title: Adaptor-mediated Lon proteolysis restricts Bacillus subtilis hyperflagellation.
abstract: The Lon AAA+ protease is a highly conserved intracellular protease that is considered an anticancer target in eukaryotic cells and a crucial virulence regulator in bacteria. Lon degrades both damaged, misfolded proteins and specific native regulators, but how Lon discriminates among a large pool of candidate targets remains unclear. Here we report that Bacillus subtilis LonA specifically degrades the master regulator of flagellar biosynthesis SwrA governed by the adaptor protein swarming motility inhibitor A (SmiA). SmiA-dependent LonA proteolysis is abrogated upon microbe-substrate contact causing SwrA protein levels to increase and elevate flagellar density above a critical threshold for swarming motility atop solid surfaces. Surface contact-dependent cellular differentiation in bacteria is rapid, and regulated proteolysis may be a general mechanism of transducing surface stimuli.
authors.affiliation: Department of Biology, Indiana University, Bloomington, IN 47405; and.
authors.forename: Sampriti
authors.initials: S
authors.lastname: Mukherjee
authors.affiliation: Department of Biology, Indiana University, Bloomington, IN 47405; and.
authors.forename: Anna C
authors.initials: AC
authors.lastname: Bree
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Massachusetts Amherst, Amherst, MA 01003.
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Biology, Indiana University, Bloomington, IN 47405; and.
authors.forename: Joyce E
authors.initials: JE
authors.lastname: Patrick
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Massachusetts Amherst, Amherst, MA 01003.
authors.forename: Peter
authors.initials: P
authors.lastname: Chien
authors.affiliation: Department of Biology, Indiana University, Bloomington, IN 47405; and dbkearns@indiana.edu.
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Kearns
mesh_terms: D001412:Bacillus subtilis / Q000166:cytology / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D005407:Flagella / Q000378:metabolism*; D008954:Models, Biological; D009068:Movement; D049070:Protease La / Q000378:metabolism*; D059748:Proteolysis
chemical_list: D001426:Bacterial Proteins; D049070:Protease La
keywords: LonA; SwrA; adaptor; flagella; regulatory proteolysis