| Primary Identifier | IPR027267 | Type | Homologous_superfamily |
| Short Name | AH/BAR_dom_sf |
| description | This superfamily represents a structural domain which consists of three α-helices, including the arfaptin homology (AH) domain and the BAR (Bin-Amphiphysin-Rvs) domain.The arfaptin homology (AH) domain is a protein domain found in a range of proteins, including arfaptins, protein kinase C-binding protein PICK1 []and mammalian 69kDa islet cell autoantigen (ICA69) []. The AH domain of arfaptin has been shown to dimerise and to bind Arf and Rho family GTPases [, ], including ARF1, a small GTPase involved in vesicle budding at the Golgi complex and immature secretory granules. The AH domain consists of three α-helices arranged as an extended antiparallel α-helical bundle. Two arfaptin AH domains associate to form a highly elongated, crescent-shaped dimer [, ].Members of the Amphiphysin protein family are key regulators in the early steps of endocytosis, involved in the formation of clathrin-coated vesicles by promoting the assembly of a protein complex at the plasma membrane and directly assist in the induction of the high curvature of the membrane at the neck of the vesicle. Amphiphysins contain a characteristic domain, known as the BAR (Bin-Amphiphysin-Rvs) domain, which is required for their in vivofunction and their ability to tubulate membranes []. The crystal structure of these proteins suggest the domain forms a crescent-shaped dimer of a three-helix coiled coil with a characteristic set of conserved hydrophobic, aromatic and hydrophilic amino acids. Proteins containing this domain have been shown to homodimerise, heterodimerise or, in a few cases, interact with small GTPases. |
