Crystal structures of the vitamin D-binding protein and its complex with actin: structural basis of the actin-scavenger system.

ABSTRACT: Actin is the most abundant protein in eukaryotic cells, but its release from cells into blood vessels can be lethal, being associated with clinical situations including hepatic necrosis and septic shock. A homeostatic mechanism, termed the actin-scavenger system, is responsible for the depolymerization and removal of actin from the circulation. During the first phase of this mechanism, gelsolin severs the actin filaments. In the second phase, the vitamin D-binding protein (DBP) traps the actin monomers, which accelerates their clearance. We have determined the crystal structures of DBP by itself and complexed with actin to 2.1 A resolution. Similar to its homologue serum albumin, DBP consists of three related domains. Yet, in DBP a strikingly different organization of the domains gives ris

SUBMITTER: Otterbein LR 

PROVIDER: S-EPMC123010 | biostudies-literature | 2002 Jun

REPOSITORIES: biostudies-literature