PMID: 9228945

Authors:

Blanchard H, Grochulski P, Li Y, Arthur JS, Davies PL, Elce JS, Cygler M

Title:

Structure of a calpain Ca(2+)-binding domain reveals a novel EF-hand and Ca(2+)-induced conformational changes.

Journal:

Nat Struct Biol. 1997 Jul;4(7):532-8.

Abstract:

The crystal structure of a Ca(2+)-binding domain (dVI) of rat m-calpain has been determined at 2.3 A resolution, both with and without bound Ca2+. The structures reveal a unique fold incorporating five EF-hand motifs per monomer, three of which bind calcium at physiological calcium concentrations, with one showing a novel EF-hand coordination pattern. This investigation gives us a first view of the calcium-induced conformational changes, and consequently an insight into the mechanism of calcium induced activation in calpain. The crystal structures reveal a dVI homodimer which provides a preliminary model for the subunit dimerization in calpain.