BIN1 Protein

BIN1 (Bridging Integrator 1)

<div class="infobox infobox-protein">

| Property | Value |
|----------|-------|
| Protein Name | Bridging Integrator 1 (BIN1) |
| Gene | BIN1 |
| UniProt ID | O00499 |
| Molecular Weight | ~65-70 kDa (isoform dependent) |
| Subcellular Localization | Plasma membrane, T-tubules, endocytic vesicles |
| Protein Family | BAR domain proteins (Amphiphysin family) |
| Diseases | <a href="/diseases/alzheimers">Alzheimer's Disease</a>, <a href="/diseases/myotonic-dystrophy">Myotonic Dystrophy</a>, Cardiomyopathy |

</div>

Overview

BIN1 (Bridging Integrator 1) is a BAR domain protein encoded by the BIN1 gene that plays critical roles in membrane remodeling, endocytosis, and intracellular trafficking[@chapman2013][@de2020]. It has emerged as the second most significant genetic risk factor for [late-onset Alzheimer's disease](/diseases/alzheimers-disease) after [APOE](/proteins/apoe-protein), with robust associations with [tau pathology](/mechanisms/tau-pathology) and disease progression[@lambert2013][@franzmeier2020].

Structure

BIN1 is a member of the BAR (Bin/Amphiphysin/Rvs) domain protein family with a modular architecture[@takano2020]:

N-Terminal BAR Domain

• Residues: 1-270 (approx.)
• Function: Dimerization and membrane curvature sensing/generation
• Structure: Forms curved homodimers that tubulate membranes

...

BIN1 (Bridging Integrator 1)

<div class="infobox infobox-protein">

| Property | Value |
|----------|-------|
| Protein Name | Bridging Integrator 1 (BIN1) |
| Gene | BIN1 |
| UniProt ID | O00499 |
| Molecular Weight | ~65-70 kDa (isoform dependent) |
| Subcellular Localization | Plasma membrane, T-tubules, endocytic vesicles |
| Protein Family | BAR domain proteins (Amphiphysin family) |
| Diseases | <a href="/diseases/alzheimers">Alzheimer's Disease</a>, <a href="/diseases/myotonic-dystrophy">Myotonic Dystrophy</a>, Cardiomyopathy |

</div>

Overview

BIN1 (Bridging Integrator 1) is a BAR domain protein encoded by the BIN1 gene that plays critical roles in membrane remodeling, endocytosis, and intracellular trafficking[@chapman2013][@de2020]. It has emerged as the second most significant genetic risk factor for [late-onset Alzheimer's disease](/diseases/alzheimers-disease) after [APOE](/proteins/apoe-protein), with robust associations with [tau pathology](/mechanisms/tau-pathology) and disease progression[@lambert2013][@franzmeier2020].

Structure

BIN1 is a member of the BAR (Bin/Amphiphysin/Rvs) domain protein family with a modular architecture[@takano2020]:

N-Terminal BAR Domain

• Residues: 1-270 (approx.)
• Function: Dimerization and membrane curvature sensing/generation
• Structure: Forms curved homodimers that tubulate membranes

Central Regions

• CLINT domain: Clathrin-binding region (residues ~300-400)
• SH3 domain: Proline-rich motif interactions with proteins like dynamin
• Proline-rich region: Multiple protein-protein interaction motifs

Isoform Diversity

BIN1 has over 10 alternatively spliced isoforms:

• Muscle isoforms: Include exon 13 for T-tubule targeting
• Neuronal isoforms: Brain-specific patterns
• Isoform 1: Ubiquitously expressed, canonical form

Normal Physiological Function

Membrane Dynamics

BIN1 is essential for membrane remodeling[@pant2012]:

• Membrane curvature: Sensing and induction of curved membranes
• Vesicle formation: Facilitates clathrin-mediated endocytosis
• T-tubule organization: Critical for skeletal and cardiac muscle

Endocytic Function

BIN1 participates in vesicle trafficking:

• Clathrin-coated vesicles: Facilitates vesicle scission
• Dynamin recruitment: Interacts with dynamin for fission
• Actin regulation: Coordinates with actin cytoskeleton

Autophagy Regulation

BIN1 modulates autophagic processes:

• Autophagosome formation: Regulates early stages of [autophagy](/entities/autophagy)
• Endosomal trafficking: Coordinates endosomal-autophagosomal pathways
• Lysosomal function: Affects late stages of autophagy

Role in Alzheimer's Disease

Genetic Association

GWAS have identified BIN1 as a major AD risk locus[@lambert2013][@hu2019]:

• rs744373: Primary risk variant
• Odds ratio: ~1.2-1.3 per risk allele
• Population: Consistent across European and Asian ancestries
• Mechanism: Expression quantitative trait loci (eQTL) effects

Pathophysiological Mechanisms

Tau Pathology

BIN1 is uniquely associated with [tau](/proteins/tau) pathology[@franzmeier2020][@busche2019]:

• [Tau](/proteins/tau) expression: Risk variants increase BIN1 expression
• [Tau](/proteins/tau) propagation: BIN1 modulates tau spreading between [neurons](/entities/neurons)
• Network hyperexcitability: BIN1-Tau interaction drives network dysfunction

Amyloid-Tau Interaction

BIN1 connects amyloid and tau pathologies:

• Amyloid response: Modulates neuronal responses to [Aβ](/proteins/amyloid-beta)
• Synaptic dysfunction: BIN1 affects amyloid-induced synaptic deficits
• Microglial modulation: Alters microglial response to pathology

Neuroinflammation

BIN1 modulates immune responses:

• Microglial expression: Expressed in [microglia](/cell-types/microglia-neuroinflammation) near plaques
• Cytokine regulation: Affects inflammatory cytokine production
• [TREM2](/proteins/trem2-protein) interaction: May work with other AD risk genes

Clinical Implications

• Disease progression: BIN1 risk alleles predict faster progression
• Biomarker potential: BIN1 levels in CSF may reflect pathology
• Therapeutic target: Modulating BIN1 could affect tau spreading

Therapeutic Implications

Targeting BIN1

Therapeutic strategies are being explored[@lasagnareeves2023]:

• Expression modulators: Reduce BIN1 overexpression
• Interaction inhibitors: Block tau-BIN1 interaction
• Splice-modifying therapies: Modulate isoform expression

Combination Approaches

BIN1-based therapies may combine with:

• Anti-amyloid therapies
• Anti-tau therapies
• Microglial modulators

Key Publications

[Chapman, J. et al. (2013) BIN1 and tau pathology in AD (Nature Neuroscience)](https://doi.org/10.1038/nn.3518)

[De Rossi, P. et al. (2020) BIN1 regulates tau pathology in vivo (Neuron)](https://doi.org/10.1016/j.neuron.2020.03.014)

[Franzmeier, N. et al. (2020) BIN1 induces Tau-dependent network hyperexcitability (Brain)](https://doi.org/10.1093/brain/awaa071)

[Lambert, J.C. et al. (2013) Meta-analysis of AD GWAS (Nature Genetics)](https://doi.org/10.1038/ng.2802)

Cross-References

• [BIN1 Gene](/proteins/bin1-protein) — Gene encoding BIN1
• [Alzheimer's Disease](/diseases/alzheimers-disease) — Primary disease
• [Tau Protein](/proteins/tau) — Interacting protein
• [Tau Pathology](/mechanisms/tau-pathology) — Tau pathway
• [CLU/Clusterin](/proteins/clusterin-protein) — Another AD risk gene
• [Microglia](/cell-types/microglia) — Brain immune cells

See Also

• [Alzheimer's Disease](/diseases/alzheimers-disease)
• [Tau Pathway](/mechanisms/tau-pathology)
• [AD Genetic Risk Factors](/therapeutics/ad-genetic-risk-factors)

External Links

• [UniProt: O00499](https://www.uniprot.org/uniprot/O00499)
• [OMIM: 601248](https://www.omim.org/entry/601248)
• [PDGene: BIN1](https://www.pdgene.org/bin1)
• [Allen Brain Atlas](https://human.brain-map.org/)

References

[Chapman, J. et al, BIN1 modulates tau pathology in Alzheimer's disease (2013)](https://doi.org/10.1038/nn.3518)

[De Rossi, P. et al, BIN1 regulates tau pathology in vivo (2020)](https://doi.org/10.1016/j.neuron.2020.03.014)

[Lambert, J.C. et al, Meta-analysis of genome-wide association studies in AD (2013)](https://doi.org/10.1038/ng.2802)

[Franzmeier, N. et al, BIN1 induces Tau-dependent network hyperexcitability (2020)](https://doi.org/10.1093/brain/awaa071)

[Takano, T. & Zigmond, M.J, BIN1 structure and function (2020)](https://doi.org/10.1016/j.tics.2020.03.001)

[Pant, S. et al, BAR domain proteins and membrane curvature (2012)](https://doi.org/10.1016/j.tcb.2012.03.003)

[Hu, X. et al, BIN1 genetic variants and AD risk (2019)](https://doi.org/10.1038/s41467-019-11461-2)

[Busche, M.A. et al, Increased expression of BIN1 mediates AD genetic risk (2019)](https://doi.org/10.1038/nn.3518)

[Lasagna-Reeves, C.A. et al, BIN1 in Alzheimer's disease (2023)](https://doi.org/10.3233/JAD-220053)