Bin1

This gene encodes several isoforms of a nucleocytoplasmic adaptor protein, one of which was initially identified as a MYC-interacting protein with features of a tumor suppressor. Isoforms that are expressed in the central nervous system may be involved in synaptic vesicle endocytosis and may interact with dynamin, synaptojanin, endophilin, and clathrin. Isoforms that are expressed in muscle and ubiquitously expressed isoforms localize to the cytoplasm and nucleus and activate a caspase-independent apoptotic process. Studies in mouse suggest that this gene plays an important role in cardiac muscle development. Alternate splicing of the gene results in several transcript variants encoding different isoforms. Aberrant splice variants expressed in tumor cell lines have also been described. [provided by RefSeq, Mar 2016]

Full Name

Bridging Integrator 1

Function

Is a key player in the control of plasma membrane curvature, membrane shaping and membrane remodeling. Required in muscle cells for the formation of T-tubules, tubular invaginations of the plasma membrane that function in depolarization-contraction coupling (PubMed:24755653).
Is a negative regulator of endocytosis (By similarity).
Is also involved in the regulation of intracellular vesicles sorting, modulation of BACE1 trafficking and the control of amyloid-beta production (PubMed:27179792).
In neuronal circuits, endocytosis regulation may influence the internalization of PHF-tau aggregates (By similarity).
May be involved in the regulation of MYC activity and the control cell proliferation (PubMed:8782822).
Has actin bundling activity and stabilizes actin filaments against depolymerization in vitro (PubMed:28893863).

Biological Process

Cytoskeleton organization Source: ARUK-UCL
Endocytosis Source: ARUK-UCL
Endosome to lysosome transport Source: ARUK-UCL
Lipid tube assembly Source: Alzheimers_University_of_Toronto
Membrane organization Source: Reactome
Negative regulation of amyloid-beta formation Source: ARUK-UCL
Negative regulation of aspartic-type endopeptidase activity involved in amyloid precursor protein catabolic process Source: ARUK-UCL
Negative regulation of calcium ion transmembrane transport via high voltage-gated calcium channel Source: ARUK-UCL
Negative regulation of potassium ion transmembrane transport Source: ARUK-UCL
Negative regulation of ventricular cardiac muscle cell action potential Source: ARUK-UCL
Nucleus localization Source: Ensembl
Nucleus organization Source: WormBase
Positive regulation of actin filament polymerization Source: ARUK-UCL
Positive regulation of apoptotic process Source: AgBase
Positive regulation of astrocyte differentiation Source: Alzheimers_University_of_Toronto
Regulation of cell cycle arrest Source: Alzheimers_University_of_Toronto
Regulation of endocytosis Source: InterPro
Regulation of heart rate by cardiac conduction Source: ARUK-UCL
Regulation of neuron differentiation Source: Alzheimers_University_of_Toronto
T-tubule organization Source: UniProtKB
Viral process Source: UniProtKB-KW

Cellular Location

Isoform BIN1: Nucleus; T-tubule; Cytoplasm; Endosome
Isoform IIA: Cytoplasm

Involvement in disease

Myopathy, centronuclear, 2 (CNM2): A congenital muscle disorder characterized by progressive muscular weakness and wasting involving mainly limb girdle, trunk, and neck muscles. It may also affect distal muscles. Weakness may be present during childhood or adolescence or may not become evident until the third decade of life. Ptosis is a frequent clinical feature. The most prominent histopathologic features include high frequency of centrally located nuclei in muscle fibers not secondary to regeneration, radial arrangement of sarcoplasmic strands around the central nuclei, and predominance and hypotrophy of type 1 fibers.
BIN1 mutations have been found in families segregating autosomal dominant centronuclear myopathy. Patients show adult-onset, mildly progressive muscle weakness affecting selected proximal muscles and all distal muscles of the lower limbs.

PTM

Phosphorylated by protein kinase C.