Bcl-2 and Bax mammalian regulators of apoptosis ave functional in Drosophila

Studies of apoptosis in C. elegans have allowed the identification of three genes, ced-3, ced-4 and ced-9. Their products constitute the components of an induction pathway of apoptosis conserved in the nematode and mammals. I n Drosophila, homologues have been found for CED-3, CED-4 and CED-9. CED-9 belongs to the Bcl-2 family which includes negative (Bcl-2) and positive (B ax) regulators of apoptosis, The recently discovered Bcl-2 family member na med Drob-1 acts as a positive regulator of cell death. To address whether a Bcl-2 anti apoptotic pathway exists in the fly, we studied the effects of expressing the mammalian genes bcl-2 in Drosophila, In embryos, expression of bcl-2 inhibits developmental and X-ray-induced apoptosis. Expressing bcl -2 or the pro-apoptotic mammalian bar in the developing eye and wing alters these structures, bcl-2 increasing the number of cells, while bar reduces the number of cells. In addition, the functional interaction between Bcl-2 and Bax is conserved. These results indicate that factors necessary for the activity of bcl-2 and bar are present in Drosophila, Therefore, a Bcl-2 pa thway for inhibition of cell death may exist in the fly.