Synapsin-1 (SYN1)

Synapsin-1 is a neuronal phosphoprotein encoded by the *SYN1* gene that is primarily associated with the cytoplasmic surface of synaptic vesicles in axon terminals of neurons[1][3][4]. It is the predominant member of the synapsin protein family and exists as two isoforms, Synapsin Ia and Synapsin Ib. Synapsin-1 plays a critical role in regulating synaptogenesis, axonogenesis, and the coordinated release of neurotransmitters by controlling the recruitment, clustering, and trafficking of synaptic vesicles[1][3][4]. Its function is tightly regulated by both phosphorylation (notably by cAMP-dependent protein kinase, calcium/calmodulin-dependent protein kinase II, mitogen-activated protein kinase, and cyclin-dependent kinase) and S-palmitoylation, which together modulate its ability to interact with F-actin and other cytoskeletal elements, thereby influencing synaptic vesicle dynamics and neurotransmission[1][2]. Mutations in the *SYN1* gene are associated with various neuropsychiatric and neurodevelopmental disorders, such as epilepsy and X-linked syndromes, including Rett syndrome[1][4].

Other names

Synapsin IBrain protein 4.1EPILXEPILX1MRX50SYN1aSYN1bSYNIsynapsin-1brain protein 4.1synapsin Ib