Bridging integrator 1 (BIN1)

Bridging integrator 1 (BIN1) is a nucleocytoplasmic adaptor protein encoded by the BIN1 gene. It belongs to the BAR adapter family of proteins that regulate membrane curvature and remodeling. Multiple isoforms exist due to alternative splicing; these isoforms have tissue-specific functions in the central nervous system, muscle cells, heart tissue, immune cells, and more. In neurons it participates in synaptic vesicle endocytosis; in muscle it is essential for T-tubule formation critical for excitation-contraction coupling. BIN1 acts as a tumor suppressor by interacting with c-MYC to inhibit its transcriptional activity. Loss or mutation of BIN1 has been implicated as a genetic risk factor for late-onset Alzheimer’s disease—likely through disruption of tau homeostasis at synapses—and causes various inherited skeletal myopathies characterized by progressive muscle weakness. In cancer biology it is frequently silenced or misspliced during malignant progression. The structure includes an N-terminal BAR domain responsible for membrane binding/tubulation and a C-terminal SH3 domain mediating interactions with other proteins such as phospholipase D isoforms.

Other names

Myc box-dependent-interacting protein 1Amphiphysin-2BIN1