Structure and calcium-binding studies of calmodulin-like domain of human non-muscle α-actinin-1.

ABSTRACT: The activity of several cytosolic proteins critically depends on the concentration of calcium ions. One important intracellular calcium-sensing protein is α-actinin-1, the major actin crosslinking protein in focal adhesions and stress fibers. The actin crosslinking activity of α-actinin-1 has been proposed to be negatively regulated by calcium, but the underlying molecular mechanisms are poorly understood. To address this, we determined the first high-resolution NMR structure of its functional calmodulin-like domain (CaMD) in calcium-bound and calcium-free form. These structures reveal that in the absence of calcium, CaMD displays a conformationally flexible ensemble that undergoes a structural change upon calcium binding, leading to limited rotation of the N- and C-terminal lobes around t

SUBMITTER: Drmota Prebil S 

PROVIDER: S-EPMC4895382 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature