title: Coordinated activation of Hsp70 chaperones.
abstract: Hsp70s are a ubiquitous family of molecular chaperones involved in many cellular processes. Two Hsp70s, Lhs1p and Kar2p, are required for protein biogenesis in the yeast endoplasmic reticulum. Here, we found that Lhs1p and Kar2p specifically interacted to couple, and coordinately regulate, their respective activities. Lhs1p stimulated Kar2p by providing a specific nucleotide exchange activity, whereas Kar2p reciprocally activated the Lhs1p adenosine triphosphatase (ATPase). The two ATPase activities are coupled, and their coordinated regulation is essential for normal function in vivo.
authors.affiliation: School of Biological Sciences, University of Manchester, Manchester M13 9PT, UK.
authors.forename: Gregor J
authors.initials: GJ
authors.lastname: Steel
authors.forename: Donna M
authors.initials: DM
authors.lastname: Fullerton
authors.forename: John R
authors.initials: JR
authors.lastname: Tyson
authors.forename: Colin J
authors.initials: CJ
authors.lastname: Stirling
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism; D020662:Guanine Nucleotide Exchange Factors; D018840:HSP70 Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000737:chemistry / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000737:chemistry / Q000378:metabolism; D018832:Molecular Chaperones / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D011485:Protein Binding; D017510:Protein Folding; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D020662:Guanine Nucleotide Exchange Factors; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; C102115:LHS1 protein, S cerevisiae; D026901:Membrane Transport Proteins; D018832:Molecular Chaperones; C074215:SEC63 protein, S cerevisiae; C513385:SIL1 protein, S cerevisiae; C418483:SIL1 protein, human; D029701:Saccharomyces cerevisiae Proteins; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases