Ca(2+) sensor involved in Ca(2+)-dependent exocytosis of secretory vesicles through Ca(2+) and phospholipid binding to the C2 domain. Ca(2+) induces binding of the C2-domains to phospholipid membranes and to assembled SNARE-complexes; both actions contribute to triggering exocytosis (By similarity). Plays a role in dendrite formation by melanocytes (PubMed:23999003). Binds 3 Ca(2+) ions per subunit. The ions are bound to the C2 domains. Homodimer; disulfide-linked via the cysteine motif. Can also form heterodimers with SYT6, SYT9 and SYT10. Expressed in melanocytes (PubMed:23999003). The cysteine motif mediates homo- or heterodimer formation via formation of disulfide bonds. The first C2 domain mediates Ca(2+)-dependent phospholipid binding. Belongs to the synaptotagmin family.