One of the hallmarks of apoptosis is the redistribution of phosphatidylserine (PS) from the
inner-to-outer plasma membrane (PM) leaflet, where it functions as a ligand for phagocyte
recognition and the suppression of inflammatory responses. The mechanism by which
apoptotic cells externalize PS has been assumed to involve" scramblases" that randomize
phospholipids across the PM bilayer. These putative activities, however, have not been
unequivocally proven to be responsible for the redistribution of lipids. Because elevated …