Intrinsically disordered caldesmon binds calmodulin via the "buttons on a string" mechanism.

ABSTRACT: We show here that chicken gizzard caldesmon (CaD) and its C-terminal domain (residues 636-771, CaD136) are intrinsically disordered proteins. The computational and experimental analyses of the wild type CaD136 and series of its single tryptophan mutants (W674A, W707A, and W737A) and a double tryptophan mutant (W674A/W707A) suggested that although the interaction of CaD136 with calmodulin (CaM) can be driven by the non-specific electrostatic attraction between these oppositely charged molecules, the specificity of CaD136-CaM binding is likely to be determined by the specific packing of important CaD136 tryptophan residues at the CaD136-CaM interface. It is suggested that this interaction can be described as the "buttons on a charged string" model, where the electrostatic attraction between

SUBMITTER: Permyakov SE 

PROVIDER: S-EPMC4582948 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature