Bcl2-L-10, a novel anti-apoptotic member of the Bcl-2 family, blocks apoptosis in the mitochondria death pathway but not in the death receptor pathway

By GenBank database searches and PCR, we have identified a novel human Bcl2 -like gene, Bcl2-L-10, which contains conserved BH4, BH1 and BH2 domains bu t lacks BH3 domain. The Bcl2-L-10 gene has been assigned to chromosome 15q2 1.2. Transfection experiments demonstrated that Bcl2-L-10 can block apoptos is induced by interleukin-3 withdrawal and Bax expression, by prevention of cytochrome C release, caspase-3 activation and mitochondrial membrane pote ntial collapse. Bcl2-L-10 cannot block TNF alpha -induced apoptosis. Furthe rmore, both the BH4 domain and the transmembrane domain of Bcl2-L-10 are ne cessary for its suppressive action on cell death. Our results demonstrated that Bcl2-L-10 is a newly detected anti-apoptotic member of the Bcl-2 famil y and that it blocks apoptosis in the mitochondrial death pathway but not i n the death receptor pathway.