Death and Survival Signals Determine Active/Inactive Conformations of Pro-apoptotic BAX, BAD, and BID Molecules

Programmed cell death plays an indispensable role inthe development and maintenance of homeostasis withinall multicellular organisms. Genetic and molecular analysis from nematodes to humans has indicated that thepathway of cellular suicide is highly conserved. Althoughthe capacity to carry out apoptosis seems to be inherent inall cells, the susceptibility to apoptosis varies markedlyand is influenced by external and cell-autonomousevents. Considerable progress has been made in identifying the molecules that regulate the apoptotic pathway ateach level. Of note, both positive and negative regulatorsoften encoded within the same family of proteins characterize the extracellular, cell surface, and intracellularsteps (Fig. 1)...