Structure of the N-terminal domain of GRP94. Basis for ligand specificity and regulation.

Published

Journal Article

GRP94, the endoplasmic reticulum (ER) paralog of the chaperone Hsp90, plays an essential role in the structural maturation or secretion of a subset of proteins destined for transport to the cell surface, such as the Toll-like receptors 2 and 4, and IgG, respectively. GRP94 differs from cytoplasmic Hsp90 by exhibiting very weak ATP binding and hydrolysis activity. GRP94 also binds selectively to a series of substituted adenosine analogs. The high resolution crystal structures at 1.75-2.1 A of the N-terminal and adjacent charged domains of GRP94 in complex with N-ethylcarboxamidoadenosine, radicicol, and 2-chlorodideoxyadenosine reveals a structural mechanism for ligand discrimination among hsp90 family members. The structures also identify a putative subdomain that may act as a ligand-responsive switch. The residues of the charged region fold into a disordered loop whose termini are ordered and continue the twisted beta sheet that forms the structural core of the N-domain. This continuation of the beta sheet past the charged domain suggests a structural basis for the association of the N-terminal and middle domains of the full-length chaperone.

Full Text

Duke Authors

Cited Authors

  • Soldano, KL; Jivan, A; Nicchitta, CV; Gewirth, DT

Published Date

  • November 28, 2003

Published In

Volume / Issue

  • 278 / 48

Start / End Page

  • 48330 - 48338

PubMed ID

  • 12970348

Pubmed Central ID

  • 12970348

International Standard Serial Number (ISSN)

  • 0021-9258

Digital Object Identifier (DOI)

  • 10.1074/jbc.M308661200

Language

  • eng

Conference Location

  • United States