Involved in synapse maturation and required for normal muscle function. Interacts with dystrophin, utrophin and the syntrophins SNTA1, SNTB1, SNTB2, SNTG1 and SNTG2. Isoforms 5 and 6 do not interact with syntrophin. Isoforms 3 and 4 do not interact with utrophin. Binds dystrobrevin binding protein 1. Interacts with MAGEE1. In peripheral nerves, colocalizes with MAGEE1 in the Schwann cell membrane. Additional isoforms seem to exist. Expressed in skeletal muscle, heart, lung and brain. Sarcolemma and neuromuscular junction in skeletal muscle. Isoform 2 is restricted to the neuromuscular junction. Isoforms 5 and 6 are only expressed in muscle. Expression of alpha-dystrobrevin is up-regulated during differentiation, with isoforms 2, 5 and 6 expressed earliest and isoform 3 and 4 expressed later. The coiled coil domain mediates the interaction with dystrophin and utrophin. Phosphorylation of isoform 2 on tyrosine kinase substrate domain present in the C-terminus. Belongs to the dystrophin family. Dystrobrevin subfamily.