Structural study of TTR-52 reveals the mechanism by which a bridging molecule mediates apoptotic cell engulfment.

ABSTRACT: During apoptosis, apoptotic cells are removed by professional phagocytes or neighboring engulfing cells either directly through phagocytic receptors or indirectly through bridging molecules that cross-link dying cells to phagocytes. However, how bridging molecules recognize "eat me" signals and phagocytic receptors to mediate engulfment remains unclear. Here, we report the structural and functional studies of Caenorhabditis elegans TTR-52, a recently identified bridging molecule that cross-links surface-exposed phosphatidylserine (PtdSer) on apoptotic cells to the CED-1 receptor on phagocytes. Crystal structure studies show that TTR-52 has an open β-barrel-like structure with some similarities to the PKCα-C2 domain. TTR-52 is proposed to bind PtdSer via an "ion-mediating" PtdSer-binding mo

SUBMITTER: Kang Y 

PROVIDER: S-EPMC3387661 | biostudies-literature | 2012 Jun

REPOSITORIES: biostudies-literature