Endophilins are a family of BAR domain-containing proteins that specialize in membrane curvature and clathrin-mediated endocytosis. They are essential for synaptic vesicle formation and trafficking.
[^1]
| Property | Value | [^2]
|----------|-------| [^3]
| **Protein Name** | Endophilin | [^4]
| **Genes** | SH3GL1 (Endophilin A1), SH3GL2 (Endophilin A2), SH3GL3 (Endophilin A3), SH3GLB1 (Endophilin B1), SH3GLB2 (Endophilin B2) |
| **UniProt IDs** | [Q9Y271](https://www.uniprot.org/uniprot/Q9Y271) (SH3GL1), [Q9UHC3](https://www.uniprot.org/uniprot/Q9UHC3) (SH3GL2), [Q9Y6K7](https://www.uniprot.org/uniprot/Q9Y6K7) (SH3GL3) |
| **Molecular Weight** | ~35-40 kDa |
| **Subcellular Localization** | Cytosolic, membrane-associated |
| **Protein Family** | BAR domain protein family |
¶ Domain Architecture
- N-terminal BAR domain: Induces and senses membrane curvature
- Linker region: Flexible connection between domains
- C-terminal SH3 domain: Binds to proline-rich motifs
- Curvature induction: BAR domain generates membrane invagination
- Tubulation: Can deform membranes into tubules
- Scar formation: Critical for endocytic pit formation
- Early events: Recruited to forming vesicles
- Cargo selection: Interacts with adaptor proteins
- Fission assistance: Helps release vesicles from membrane
- SH3 domain interactions: Binds to dynamin, synaptojanin, actin regulators
- Endophilin A2: Major isoform in brain, essential for synaptic function
- Parkinson's disease: Endophilin A1 is cleaved by parkin
- Alzheimer's disease: Alters APP internalization
- Huntington's disease: Dysregulated in HD brains
- Oncogenic properties: Overexpression in several cancers
- Cell proliferation: Regulates growth factor receptors