The C. elegans Cell Corpse Engulfment Gene ced-7 Encodes a Protein Similar to ABC Transporters

The C. elegans gene ced-7 functions in the engulfment of cell corpses during programmed cell death. We report that the CED-7 protein has sequence similarity to ABC transporters, is broadly expressed during embryogenesis, and is localized to the plasma membrane. Mosaic analysis revealed that ced-7 functions in both dying cells and engulfing cells during the engulfment process. We propose that CED-7 functions to translocate molecules that mediate homotypic adhesion between the cell surfaces of the dying and engulfing cells. Like CED-7, the mammalian ABC transporter ABC1 has been implicated in the engulfment of cell corpses, suggesting that CED-7 and ABC1 may be functionally similar and that the molecular mechanism underlying cell corpse engulfment during programmed cell death may be conserved from nematodes to mammals.