title: Activation of the ATPase activity of hsp90 by the stress-regulated cochaperone aha1.
abstract: Client protein activation by Hsp90 involves a plethora of cochaperones whose roles are poorly defined. A ubiquitous family of stress-regulated proteins have been identified (Aha1, activator of Hsp90 ATPase) that bind directly to Hsp90 and are required for the in vivo Hsp90-dependent activation of clients such as v-Src, implicating them as cochaperones of the Hsp90 system. In vitro, Aha1 and its shorter homolog, Hch1, stimulate the inherent ATPase activity of yeast and human Hsp90. The identification of these Hsp90 cochaperone activators adds to the complex roles of cochaperones in regulating the ATPase-coupled conformational changes of the Hsp90 chaperone cycle.
authors.affiliation: Division of Life Sciences, Franklin-Wilkins Building, 150 Stamford Street, SE1 9NN, London, United Kingdom
authors.forename: Barry
authors.initials: B
authors.lastname: Panaretou
authors.forename: Giuliano
authors.initials: G
authors.lastname: Siligardi
authors.forename: Philippe
authors.initials: P
authors.lastname: Meyer
authors.forename: Alison
authors.initials: A
authors.lastname: Maloney
authors.forename: Janis K
authors.initials: JK
authors.lastname: Sullivan
authors.forename: Shradha
authors.initials: S
authors.lastname: Singh
authors.forename: Stefan H
authors.initials: SH
authors.lastname: Millson
authors.forename: Paul A
authors.initials: PA
authors.lastname: Clarke
authors.forename: Soren
authors.initials: S
authors.lastname: Naaby-Hansen
authors.forename: Rob
authors.initials: R
authors.lastname: Stein
authors.forename: Rainer
authors.initials: R
authors.lastname: Cramer
authors.forename: Mehdi
authors.initials: M
authors.lastname: Mollapour
authors.forename: Paul
authors.initials: P
authors.lastname: Workman
authors.forename: Peter W
authors.initials: PW
authors.lastname: Piper
authors.forename: Laurence H
authors.initials: LH
authors.lastname: Pearl
authors.forename: Chrisostomos
authors.initials: C
authors.lastname: Prodromou
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism*; D002461:Cell Line, Transformed; D002503:Centromere / Q000235:genetics; D002942:Circular Dichroism; D003001:Cloning, Molecular; D016391:Genes, src; D005822:Genetic Vectors; D018841:HSP90 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D018832:Molecular Chaperones / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D015688:Oncogene Protein pp60(v-src) / Q000378:metabolism; D010641:Phenotype; D011994:Recombinant Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000502:physiology; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
chemical_list: D018841:HSP90 Heat-Shock Proteins; D018832:Molecular Chaperones; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D015688:Oncogene Protein pp60(v-src); D000251:Adenosine Triphosphatases