Extended synaptotagmin-2 (Esyt2)

Tethers the endoplasmic reticulum to the cell membrane and promotes the formation of appositions between the endoplasmic reticulum and the cell membrane. Binds glycerophospholipids in a barrel-like domain and might play a role in cellular lipid transport.

Plays a role in FGF signaling via its role in the rapid internalization of FGFR1 that's been activated by FGF1 binding; this occurs most likely through the AP-2 complex (By similarity). .