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1xqr
From Proteopedia
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Crystal structure of the HspBP1 core domain
Overview
HspBP1 belongs to a family of eukaryotic proteins recently identified as, nucleotide exchange factors for Hsp70. We show that the S. cerevisiae, ortholog of HspBP1, Fes1p, is required for efficient protein folding in, the cytosol at 37 degrees C. The crystal structure of HspBP1, alone and, complexed with part of the Hsp70 ATPase domain, reveals a mechanism for, its function distinct from that of BAG-1 or GrpE, previously characterized, nucleotide exchange factors of Hsp70. HspBP1 has a curved, all, alpha-helical fold containing four armadillo-like repeats unlike the other, nucleotide exchange factors. The concave face of HspBP1 embraces lobe II, of the ATPase domain, and a steric conflict displaces lobe I, reducing the, affinity for nucleotide. In contrast, BAG-1 and GrpE trigger a conserved, conformational change in lobe II of the ATPase domain. Thus, nucleotide, exchange on eukaryotic Hsp70 occurs through two distinct mechanisms.
About this Structure
1XQR is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Regulation of Hsp70 function by HspBP1: structural analysis reveals an alternate mechanism for Hsp70 nucleotide exchange., Shomura Y, Dragovic Z, Chang HC, Tzvetkov N, Young JC, Brodsky JL, Guerriero V, Hartl FU, Bracher A, Mol Cell. 2005 Feb 4;17(3):367-79. PMID:15694338
Page seeded by OCA on Mon Nov 12 20:09:46 2007
