1h1v

From Proteopedia

proteopedia linkproteopedia link

spinqualitylabelsall models 1h1v, resolution 2.99Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

GELSOLIN G4-G6/ACTIN COMPLEX

Contents 1 Overview 2 Disease 3 About this Structure 4 Reference

Overview

Gelsolin participates in the reorganization of the actin cytoskeleton that, is required during such phenomena as cell movement, cytokinesis, and, apoptosis. It consists of six structurally similar domains, G1-G6, which, are arranged at resting intracellular levels of calcium ion so as to, obscure the three actin-binding surfaces. Elevation of Ca(2+), concentrations releases latches within the constrained structure and, produces large shifts in the relative positioning of the domains, permitting gelsolin to bind to and sever actin filaments. How Ca(2+) is, able to activate gelsolin has been a major question concerning the, function of this protein. We present the improved structure of the, C-terminal half of gelsolin bound to monomeric actin at 3.0 A resolution., Two classes of Ca(2+)-binding site are evident on gelsolin: type 1 sites, share coordination of Ca(2+) with actin, while type 2 sites are wholly, contained within gelsolin. This structure of the complex reveals the, locations of two novel metal ion-binding sites in domains G5 and G6, respectively. We identify both as type 2 sites. The absolute conservation, of the type 2 calcium-ligating residues across the six domains of gelsolin, suggests that this site exists in each of the domains. In total, gelsolin, has the potential to bind eight calcium ions, two type 1 and six type 2., The function of the type 2 sites is to facilitate structural, rearrangements within gelsolin as part of the activation and actin-binding, and severing processes. We propose the novel type 2 site in G6 to be the, critical site that initiates overall activation of gelsolin by releasing, the tail latch that locks calcium-free gelsolin in a conformation unable, to bind actin.

Disease

Known disease associated with this structure: Amyloidosis, Finnish type OMIM:[137350]

About this Structure

1H1V is a Protein complex structure of sequences from Homo sapiens and Oryctolagus cuniculus with CA and ATP as ligands. This structure superseeds the now removed PDB entry 1DB0. Structure known Active Site: CA1. Full crystallographic information is available from OCA.

Reference

The calcium activation of gelsolin: insights from the 3A structure of the G4-G6/actin complex., Choe H, Burtnick LD, Mejillano M, Yin HL, Robinson RC, Choe S, J Mol Biol. 2002 Dec 6;324(4):691-702. PMID:12460571

Page seeded by OCA on Mon Nov 12 17:11:42 2007