| Primary Identifier | IPR037741 | Type | Domain |
| Short Name | C2B_Synaptotagmin-7 |
| description | Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains []. Synaptotagmin 7, a member of class 2 synaptotagmins, is located in presynaptic plasma membranes in neurons, dense-core vesicles in endocrine cells, and lysosomes in fibroblasts. It has been shown to play a role in regulation of Ca2+-dependent lysosomal exocytosis in fibroblasts and also functions as a vesicular Ca2+-sensor [, ]. It is distinguished from the other synaptotagmins by having over 12 splice forms [].Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10) []. The general function of C2 domains in these is to mediate Ca2+-triggered binding of the protein to a membrane [].C2 domains fold into an 8-standed β-sandwich that can adopt 2 structural arrangements: type I and type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. This entry represents the second C2 repeat, C2B, and has a type-I topology []. |
