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Actin-DBP: the perfect structural fit?

Christel Verboven·Ilse Bogaerts·Etienne Waelkens·Anja Rabijns·Hugo Van Baelen·Roger Bouillon·Camiel De Ranter
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Abstract

The multifunctional vitamin D binding protein (DBP) is an actin-sequestering protein present in blood. The crystal structure of the actin-DBP complex was determined at 2.4 A resolution. DBP binds to actin subdomains 1 and 3 and occludes the cleft at the interface between these subdomains. Most remarkably, DBP demonstrates an unusually large actin-binding interface, far exceeding the binding-interface areas reported for other actin-binding proteins such as profilin, DNase I and gelsolin. The fast-growing side of actin monomers is blocked completely through a perfect structural fit with DBP, demonstrating how DBP effectively interferes with actin-filament formation. It establishes DBP as the hitherto best actin-sequestering protein and highlights its key role in suppressing and preventing extracellular actin polymerization.

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ActinsAnimalsBinding SitesCrystallography, X-RayHumansHydrogen BondingMicrofilament ProteinsModels, MolecularProtein ConformationProtein Structure, TertiaryRabbitsVitamin D-Binding ProteinJournal ArticleResearch Support, Non-U.S. Gov't

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Christel Verboven, Ilse Bogaerts, Etienne Waelkens, Anja Rabijns, Hugo Van Baelen, Roger Bouillon, Camiel De Ranter. 2003-01-23. Actin-DBP: the perfect structural fit?. https://doi.org/10.1107/s0907444902021455

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