title: Structure and mechanism of the Hsp90 molecular chaperone machinery.
abstract: Heat shock protein 90 (Hsp90) is a molecular chaperone essential for activating many signaling proteins in the eukaryotic cell. Biochemical and structural analysis of Hsp90 has revealed a complex mechanism of ATPase-coupled conformational changes and interactions with cochaperone proteins, which facilitate activation of Hsp90's diverse "clientele." Despite recent progress, key aspects of the ATPase-coupled mechanism of Hsp90 remain controversial, and the nature of the changes, engendered by Hsp90 in client proteins, is largely unknown. Here, we discuss present knowledge of Hsp90 structure and function gleaned from crystallographic studies of individual domains and recent progress in obtaining a structure for the ATP-bound conformation of the intact dimeric chaperone. Additionally, we describe the roles of the plethora of cochaperones with which Hsp90 cooperates and growing insights into their biochemical mechanisms, which come from crystal structures of Hsp90 cochaperone complexes.
authors.affiliation: Section of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, London SW3 6JB, United Kingdom. laurence.pearl@icr.ac.uk
authors.forename: Laurence H
authors.initials: LH
authors.lastname: Pearl
authors.forename: Chrisostomos
authors.initials: C
authors.lastname: Prodromou
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001665:Binding Sites; D019281:Dimerization; D004789:Enzyme Activation; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018841:HSP90 Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D046912:Multiprotein Complexes; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary
chemical_list: D005656:Fungal Proteins; D018841:HSP90 Heat-Shock Proteins; D018832:Molecular Chaperones; D046912:Multiprotein Complexes; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases