REACTIVE OXYGEN SPECIES AND PROGRAMMED CELL-DEATH

Bcl-2 is a proto-oncoprotein with apparently one function - to suppres s programmed cell death (PCD) - yet how it does so remains a mystery. Several authors have proposed that Bcl-2 is an antioxidant that suppre sses the formation or action of reactive oxygen species (ROS) and in t his way inhibits pCD(1-4). However, three recent papers indicate that ROS are not required for PCD and that Bcl-2 can protect against cell d eath even under conditions where ROS are unlikely to be produced(5-7).