PMID: 20383143 , Related PDB id: 3LUE
Galkin VE, Orlova A, Salmazo A, Djinovic-Carugo K, Egelman EH
Opening of tandem calponin homology domains regulates their affinity for F-actin.
Nat Struct Mol Biol. 2010 May;17(5):614-6. Epub 2010 Apr 11.
Many actin-binding proteins contain calponin homology (CH) domains, but the manner in which these domains interact with F-actin has been controversial. Crystal structures have shown the tandem CH domains of alpha-actinin to be in a compact, closed conformation, but the interpretations of complexes of such tandem CH domains with F-actin have been ambiguous. We show that the tandem CH domains of alpha-actinin bind F-actin in an open conformation, explaining mutations that cause human diseases and suggesting that the opening of these domains may be one of the main regulatory mechanisms for proteins with tandem CH domains.