title: AAA+ chaperone ClpX regulates dynamics of prokaryotic cytoskeletal protein FtsZ.
abstract: AAA(+) chaperone ClpX has been suggested to be a modulator of prokaryotic cytoskeletal protein FtsZ, but the details of recognition and remodeling of FtsZ by ClpX are largely unknown. In this study, we have extensively investigated the nature of FtsZ polymers and mechanisms of ClpX-regulated FtsZ polymer dynamics. We found that FtsZ polymerization is inhibited by ClpX in an ATP-independent manner and that the N-terminal domain of ClpX plays a crucial role for the inhibition of FtsZ polymerization. Single molecule analysis with high speed atomic force microscopy directly revealed that FtsZ polymer is in a dynamic equilibrium between polymerization and depolymerization on a time scale of several seconds. ClpX disassembles FtsZ polymers presumably by blocking reassembly of FtsZ. Furthermore, Escherichia coli cells overproducing ClpX and N-terminal domain of ClpX show filamentous morphology with abnormal localization of FtsZ. These data together suggest that ClpX modulates FtsZ polymer dynamics in an ATP-independent fashion, which is achieved by interaction between the N-terminal domain of ClpX and FtsZ monomers or oligomers.
authors.affiliation: Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Kumamoto 860-0811, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Sugimoto
authors.forename: Kunitoshi
authors.initials: K
authors.lastname: Yamanaka
authors.forename: Shingo
authors.initials: S
authors.lastname: Nishikori
authors.forename: Atsushi
authors.initials: A
authors.lastname: Miyagi
authors.forename: Toshio
authors.initials: T
authors.lastname: Ando
authors.forename: Teru
authors.initials: T
authors.lastname: Ogura
mesh_terms: D000074183:ATPases Associated with Diverse Cellular Activities; D000251:Adenosine Triphosphatases / Q000502:physiology*; D000255:Adenosine Triphosphate; D001426:Bacterial Proteins / Q000378:metabolism*; D001665:Binding Sites; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D049071:Endopeptidase Clp / Q000502:physiology*; D004926:Escherichia coli / Q000166:cytology; D029968:Escherichia coli Proteins / Q000502:physiology*; D018625:Microscopy, Atomic Force; D018832:Molecular Chaperones / Q000502:physiology*; D055503:Protein Multimerization
chemical_list: D001426:Bacterial Proteins; D003598:Cytoskeletal Proteins; D029968:Escherichia coli Proteins; C071525:FtsZ protein, Bacteria; D018832:Molecular Chaperones; D000255:Adenosine Triphosphate; D049071:Endopeptidase Clp; D000251:Adenosine Triphosphatases; C088072:ClpX protein, E coli; D000074183:ATPases Associated with Diverse Cellular Activities