Summary for 1H1V
| Entry DOI | 10.2210/pdb1h1v/pdb |
| Related | 1C0F 1C0G 1D4X 1DEJ 1DGA 1EQY 1ESV 1KCQ 1SOL 1YAG 1YVN |
| Descriptor | ACTIN, GELSOLIN, CALCIUM ION, ... (5 entities in total) |
| Functional Keywords | actin-binding, severing, capping, calcium, amyloid, muscle contraction |
| Biological source | HOMO SAPIENS (HUMAN) More |
| Total number of polymer chains | 2 |
| Total formula weight | 78977.73 |
| Authors | Choe, H.,Burtnick, L.D.,Mejillano, M.,Yin, H.L.,Robinson, R.C.,Choe, S. (deposition date: 2002-07-23, release date: 2003-01-24, Last modification date: 2023-12-13) |
| Primary citation | Choe, H.,Burtnick, L.D.,Mejillano, M.,Yin, H.L.,Robinson, R.C.,Choe, S. The Calcium Activation of Gelsolin:Insights from the 3A Structure of the G4-G6/Actin Complex J.Mol.Biol., 324:691-, 2002 Cited by PubMed Abstract: 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. PubMed: 12460571DOI: 10.1016/S0022-2836(02)01131-2 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.99 Å) |
Structure validation
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