Expression of Bcl-x(S) in Xenopus oocytes induces BH3-dependent and caspase-dependent cytochrome c release and apoptosis.

The mechanism of action of pro-apoptotic proteins is difficult to study in vivo because of their death effect, which makes it problematic to obtain sufficient homogeneous experimental material for biochemical analysis. We show here that pro-apoptotic genes expressed in Xenopus oocytes constitute a useful in vivo system for studying their mechanism of action. In the present study, we used this system to study the death effects of Bcl-x(S), a pro-apoptotic member of the Bcl-2 family.