Bridging integrator 3Bridging integrator 3 is a protein. In humans it is encoded by the BIN3 gene.FunctionThe product of this gene is a member of the BAR domain protein family. The encoded protein is composed solely of a BAR domain which is predicted to form coiled coil structures and is proposed to mediate dimerization, sense and induce membrane curvature, and bind small GTPases. BAR domain proteins have been implicated in endocytosis, intracellular transport, and a diverse set of other processes.