Synaptotagmin (SYT (or Syt when referring to individual isoforms, e.g., Syt1))

Synaptotagmins are a protein family consisting of at least 16 vertebrate isoforms, characterized by an N-terminal transmembrane domain and two cytoplasmic C2 domains. Canonical isoforms, such as Synaptotagmin-1 (Syt1), act as low-affinity, fast calcium sensors essential for triggering rapid, synchronous neurotransmitter release at synapses via the exocytosis of synaptic vesicles. These calcium-dependent processes are mediated by synaptotagmin's direct interactions with SNARE complex proteins and phospholipid membranes, causing membrane fusion and neurotransmitter release. Distinct isoforms differ in their calcium-binding properties and kinetics, with Syt1 governing fast transmission and Syt7 mediating slower, asynchronous release. Mutations in Synaptotagmin-1 can result in severe neurodevelopmental disorders, emphasizing its crucial role in brain function. The protein is present in both vertebrates and invertebrates and is conserved across species. Synaptotagmin is widely used as a cellular marker and research tool in studies of synaptogenesis, neurotransmission, and nerve development. Although not yet a routine clinical target, emerging research links its modulation with potential treatments for certain brain diseases.

Other names

Synaptotagmin familySynaptotagmin-1 (Syt1)Synaptotagmin-2 (Syt2), etc.p65 (historically for Syt1)

Potassium channel antagonist (used to rescue dominant-negative phenotypes in Synaptotagmin-1 mutations) In theory, drugs may target Ca2+ sensing, membrane fusion, or SNARE complex interactions, but none are broadly validated in humans