EFFECT OF ANTI-APOPTOTIC GENES AND PEPTIDE INHIBITORS ON CYTOPLASMIC ACIDIFICATION DURING APOPTOSIS

Cytoplasmic acidification has been shown to occur during the apoptotic process of cell death although its relation with other events in the process are not yet clear. AK-5 tumor cells have been shown to undergo apoptosis upon treatment with stimuli like dexamethasone (1 mu M) or with serum from animals that reject AK-5 tumor. The current study was designed to measure the extent of cytoplasmic acidification during apo ptosis in AK-5 cells and to study the effect of antiapopoptic genes an d peptide inhibitors on cytoplasmic acidification, Our results show th at AK-5 cells when triggered into apoptosis show intracellular acidifi cation by about 0.2 pH units and this is prevented when cells are trea ted with peptide inhibitors, In addition cytoplasmic acidification doe s not occur when AK-5 cells are transfected with anti-apoptotic genes Nedd-2 A.S, Crm A or bcl-2 which inhibit apoptosis. (C) 1997 Federatio n of European Biochemical Societies.