BCL-2 mutants with restricted sub-cellular location reveal spatially distinct pathways for apoptosis in different cell types

Human Bcl-2 is located in multiple intracellular membranes when expressed in MDCK and Rat 1/myc cells. We restricted expression to the endoplasmic reticulum or mitochondria by exchanging the Bcl-2 carboxyl-terminal insertion sequence for an equivalent sequence from cytochrome b5 or ActA, respectively. MDCK cells are protected from serum deprivation induced apoptosis by both wild-type Bcl-2 and the mutant targeted to mitochondria but not by the …