The present invention relates generally to novel molecules capable of, inter alia, modulating apoptosis in mammalian cells and to genetic sequences encoding same. More particularly, the present invention relates to a novel member of the Bcl-2 family of proteins, referred to herein as "Bim", and to genetic sequences encoding same. The molecules of the present invention are useful, for example, in therapy, diagnosis, antibody generation and as a screening tool for therapeutic agents capable of modulating physiological cell death or survival and/or modulating cell cycle entry.