2o1t
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Structure of Middle plus C-terminal domains (M+C) of GRP94
OverviewOverview
GRP94, an essential endoplasmic reticulum chaperone, is required for the, conformational maturation of proteins destined for cell-surface display or, export. The extent to which GRP94 and its cytosolic paralog, Hsp90, share, a common mechanism remains controversial. GRP94 has not been shown, conclusively to hydrolyze ATP or bind cochaperones, and both activities, by contrast, result in conformational changes and N-terminal dimerization, in Hsp90 that are critical for its function. Here, we report the 2.4 A, crystal structure of mammalian GRP94 in complex with AMPPNP and ADP. The, chaperone is conformationally insensitive to the identity of the bound, nucleotide, adopting a "twisted V" conformation that precludes N-terminal, domain dimerization. We also present conclusive evidence that GRP94, possesses ATPase activity. Our observations provide a structural, explanation for GRP94's observed rate of ATP hydrolysis and suggest a, model for the role of ATP binding and hydrolysis in the GRP94 chaperone, cycle.
About this StructureAbout this Structure
2O1T is a Single protein structure of sequence from Canis lupus familiaris. Full crystallographic information is available from OCA.
ReferenceReference
Structures of GRP94-Nucleotide Complexes Reveal Mechanistic Differences between the hsp90 Chaperones., Dollins DE, Warren JJ, Immormino RM, Gewirth DT, Mol Cell. 2007 Oct 12;28(1):41-56. PMID:17936703
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