Synaptotagmin-2 (SYT2) is a synaptic vesicle membrane protein that functions as a calcium sensor and plays a crucial role in fast Ca虏鈦?-dependent neurotransmitter release at the presynaptic nerve terminal. It is widely expressed in the brain and is particularly important at the neuromuscular junction. SYT2 contains two calcium-binding domains, C2A and C2B, with the C2B domain being essential for mediating vesicle fusion and neurotransmitter release. Mutations in the SYT2 gene can lead to various neuromuscular disorders, such as distal motor neuropathy and myasthenic syndrome, which are often associated with presynaptic dysfunction at the neuromuscular junction. Recent studies have also shown that SYT2 can serve as a reliable marker for analyzing the development and plasticity of inhibitory synapses formed by parvalbumin-positive interneurons in the visual cortex.