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X-ray structure of the human calreticulin globular domain reveals a peptide-binding area and suggests a multi-molecular mechanism.

ABSTRACT: In the endoplasmic reticulum, calreticulin acts as a chaperone and a Ca(2+)-signalling protein. At the cell surface, it mediates numerous important biological effects. The crystal structure of the human calreticulin globular domain was solved at 1.55 Å resolution. Interactions of the flexible N-terminal extension with the edge of the lectin site are consistently observed, revealing a hitherto unidentified peptide-binding site. A calreticulin molecular zipper, observed in all crystal lattices, could further extend this site by creating a binding cavity lined by hydrophobic residues. These data thus provide a first structural insight into the lectin-independent binding properties of calreticulin and suggest new working hypotheses, including that of a multi-molecular mechanism.

SUBMITTER: Chouquet A

PROVIDER: S-EPMC3057994 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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X-ray structure of the human calreticulin globular domain reveals a peptide-binding area and suggests a multi-molecular mechanism.

Chouquet Anne A Païdassi Helena H Ling Wai Li WL Frachet Philippe P Houen Gunnar G Arlaud Gérard J GJ Gaboriaud Christine C

PloS one 20110315 3

In the endoplasmic reticulum, calreticulin acts as a chaperone and a Ca(2+)-signalling protein. At the cell surface, it mediates numerous important biological effects. The crystal structure of the human calreticulin globular domain was solved at 1.55 Å resolution. Interactions of the flexible N-terminal extension with the edge of the lectin site are consistently observed, revealing a hitherto unidentified peptide-binding site. A calreticulin molecular zipper, observed in all crystal lattices, co ...[more]

PMID: 21423620

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