INCREASED CELL-SURFACE EXPOSURE OF FUCOSE RESIDUES IS A LATE EVENT INAPOPTOSIS

Apoptosis is a well defined physiological process characterised by man y specific features including DNA fragmentation and protease activatio n. Cell membrane-associated changes such as the altered exposure of ph osphatidylserine and glycosylation patterns have also been described. We investigate here the change in exposure of surface alpha-L-fucose r esidues during thymocyte and P815 cell apoptosis. We show that apoptos is in these cells induced by dexamethasone, gliotoxin or thapsigargin was associated with an increase in the exposure of terminal fucose res idues. Furthermore, this increase in fucose exposure occurred late in the apoptotic process. The observation of increased fucose exposure in two different cell types by three different apoptosis-inducing agents suggests it may be part of the normal apoptotic process. (C) 1998 Aca demic Press.