Stonin-2 is a stonin family protein involved in synaptic vesicle recycling. It is an adaptor-like protein that serves as a linker between the endocytic proteins AP-2 and Eps15, and the calcium-sensing synaptic vesicle (SV) protein synaptotagmin 1 [, , ].Stonin family members are conserved clathrin adaptor complex AP-2mu-related factors that may act as cargo-specific sorting adaptors in endocytosis. They are conserved from C. elegans to humans, but are not found in prokaryotes or yeasts. Their protein structure consists of an N-terminal proline- and serine-rich domain, a central stonin homology domain (SHD), and a C-terminal Mu homology domain that may adopt a conformation similar to the C-terminal sorting signal binding domain of AP-2mu (C-mu2) [].
