Background information
BAR proteins are characterized by a common N-terminal BAR (bin, amphiphysin and Rvs161/167) domain and are recognized as adaptor proteins that are involved in many cellular processes. BIN1 and BIN2 are BAR proteins that share 61% sequence similarity. BIN1 (Bridging integrator 1) is a ubiquitously expressed regulatory protein for synaptic vesicle endocytosis. BIN1 also interacts with the transcription factors c-Myc and MyoD, potentially functioning as a tumor suppressor. BIN2, also known as Breast cancer-associated protein 1, is a 565 amino acid protein that interacts with BIN1. In contrast to BIN1, BIN2 lacks tumor suppressor features as well as a c-Myc interacting region. BIN2 shows preferred expression in tissues of hematopoietic origin, with high levels found in spleen, thymus, colon, placenta, lymphoid and granulocytic cells. There are two isoforms of BIN2 that are produced as a result of alternative splicing events.