SYT13 (synaptotagmin 13) is a non-canonical synaptotagmin family member that functions as a calcium-insensitive regulator of vesicular transport and exocytosis 1. Unlike canonical synaptotagmins, SYT13 lacks calcium-binding sites but localizes to insulin granules and synaptic vesicles, where it regulates exocytosis through SNARE complex interactions 2. In motor neurons, SYT13 serves as a resilience factor: it is preferentially expressed in resistant motor neuron subtypes and heterozygous SYT13 loss triggers ALS-like neurodegenerative phenotypes with TP53-mediated apoptosis 34. SYT13 overexpression in ALS and SMA patient neurons improves survival and extends lifespan in animal models 3. In synucleinopathies, abnormal phosphorylated α-synuclein binds SYT13, impairing extracellular vesicle release and reducing synaptic function 5. In metabolic contexts, SYT13 knockdown impairs glucose-stimulated insulin secretion 2. Conversely, SYT13 is oncogenic in multiple cancers—upregulation promotes proliferation, migration, and metastasis in esophageal, gastric, and cervical cancers through PI3K-Akt pathway activation 678. Thus, SYT13 represents a promising therapeutic target for both neurodegeneration and cancer.