The BH3 domain is a short motif known to bind to Bcl-xLs. This interaction is important in apoptosis.

1: DAP-kinase-mediated phosphorylation on the BH3 domain of beclin 1 promotes dissociation of beclin 1 from Bcl-XL and induction of autophagy. Zalckvar E, Berissi H, Mizrachy L, Idelchuk Y, Koren I, Eisenstein M, Sabanay H, Pinkas-Kramarski R, Kimchi A; EMBO Rep. 2009;10:285-292. PMID:19180116