title: Inter-ring rotations of AAA ATPase p97 revealed by electron cryomicroscopy.
abstract: The type II AAA+ protein p97 is involved in numerous cellular activities, including endoplasmic reticulum-associated degradation, transcription activation, membrane fusion and cell-cycle control. These activities are at least in part regulated by the ubiquitin system, in which p97 is thought to target ubiquitylated protein substrates within macromolecular complexes and assist in their extraction or disassembly. Although ATPase activity is essential for p97 function, little is known about how ATP binding or hydrolysis is coupled with p97 conformational changes and substrate remodelling. Here, we have used single-particle electron cryomicroscopy (cryo-EM) to study the effect of nucleotides on p97 conformation. We have identified conformational heterogeneity within the cryo-EM datasets from which we have resolved two major p97 conformations. A comparison of conformations reveals inter-ring rotations upon nucleotide binding and hydrolysis that may be linked to the remodelling of target protein complexes.
authors.affiliation: Centre for Structural Biology, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK.
authors.forename: Heidi O
authors.initials: HO
authors.lastname: Yeung
authors.forename: Andreas
authors.initials: A
authors.lastname: Förster
authors.forename: Cecilia
authors.initials: C
authors.lastname: Bebeacua
authors.forename: Hajime
authors.initials: H
authors.lastname: Niwa
authors.forename: Caroline
authors.initials: C
authors.lastname: Ewens
authors.forename: Ciarán
authors.initials: C
authors.lastname: McKeown
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Zhang
authors.forename: Paul S
authors.initials: PS
authors.lastname: Freemont
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D001665:Binding Sites; D020285:Cryoelectron Microscopy; D060746:Endoplasmic Reticulum-Associated Degradation; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry; D018625:Microscopy, Atomic Force; D008958:Models, Molecular; D062105:Molecular Docking Simulation; D009154:Mutation; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics
chemical_list: D009687:Nuclear Proteins; D011994:Recombinant Proteins; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; C404942:p97 ATPase
keywords: ATPase; conformational changes; electron microscopy; mechanism; structure