Protein Domain : Amphiphysin, isoform 1 IPR003017

Type	Family
Description	Amphiphysins belong to the expanding BAR (Bin-Amphiphysin-Rvsp) family proteins, all members of which share a highly conserved N-terminal BAR domain, which has predicted coiled-coil structures required for amphiphysin dimerisation and plasma membrane interaction [ ]. Almost all members also share a conserved C-terminal Src homology 3 (SH3) domain, which mediates their interactions with the GTPase dynamin and the inositol-5'-phosphatase synaptojanin 1 in vertebrates and with actin in yeast. The central region of all these proteins is most variable. In mammals, the central region of amphiphysin I and amphiphysin IIa contains a proline-arginine-rich region for endophilin binding and a CLAP domain, for binding to clathrin and AP-2. The interactions mediated by both the central and C-terminal domains are believed to be modulated by protein phosphorylation [ , ].Amphiphysins are proteins involved in clathrin-mediated endocytosis clathrin-mediated endocytosis, actin function, and signalling pathways [ , ].Amphiphysin 1 was first identified in 1992 as a brain protein that was partially-associated with synaptic vesicles. Following its cloning, it was also realised to be a human auto-antigen that is detected in a rare neurological disease, Stiff-Man Syndrome, and also in certain types of cancer [ ]. Amphiphysin 1 senses and facilitates membrane curvature to mediate synaptic vesicles invagination and fission during newly retrieved presynaptic vesicle formation and also acts as a linker protein binding with dynamin, clathrin, Amphiphysin II, and other dephosphins in the clathrin-coated complex. Amphiphysin 1 is cleaved an asparagine endopeptidase (AEP), which generates a fragment that increases with aging. This fragment disrupts the normal endocytic function of Amphiphysin 1, leading to synaptic dysfunction, as it activates CDK5 inducing tau hyperphosphorylation. Therefore, Amphiphysin 1 posttranslational modification contributes to pathogenesis of Alzheimer's disease, being the AEP a therapeutic target [].
Short Name	Amphiphysin_1