Bmf: A proapoptotic BH3-only protein regulated by interaction with the myosin V actin motor complex, activated by anoikis

Bcl-2 family members bearing only the BH3 domain are essential inducers of apoptosis. We identified a BH3-only protein, Bmf, and show that its BH3 dom ain is required both for binding to prosurvival Bcl-2 proteins and for trig gering apoptosis. In healthy cells, Bmf is sequestered to myosin V motors b y association with dynein light chain 2. Certain damage signals, such as lo ss of cell attachment (anoikis), unleash Bmf, allowing it to translocate an d bind prosurvival. Bcl-2 proteins. Thus, at least two mammalian BH3-only p roteins, Bmf and Bim, function to sense intracellular damage by their local ization to distinct cytoskeletal structures.