SYT17 (synaptotagmin-17) is a calcium-dependent phospholipid-binding protein involved in vesicle-mediated transport and exocytosis regulation. As a member of the synaptotagmin family, SYT17 functions as a calcium ion sensor mediating SNARE binding and regulating calcium-dependent exocytosis 1. The protein plays a role in dendrite formation by melanocytes and participates in the regulation of postsynaptic neurotransmitter receptor internalization at glutamatergic synapses. SYT17 has emerged as a significant biomarker in kidney transplantation. Urinary exosomal SYT17 levels are elevated in chr16 active antibody-mediated rejection (CAAMR) and correlate with activation of the IL-6 amplifier inflammatory pathway, with increased SYT17 expression detected in renal tubule cells of CAAMR patients 2. SYT17 is recognized as a kidney-specific marker in urinary extracellular vesicles for detecting allograft dysfunction and various post-transplant complications 3. Clinically, SYT17 expression is modulated by therapeutic interventions: baricitinib treatment in systemic sclerosis patients resulted in SYT17 upregulation as part of immune response normalization 4. Additionally, SYT17 was identified as a differentially expressed gene associated with therapeutic response in dendritic cell vaccination for non-Hodgkin lymphoma and as a PARP1 target gene in melanoma pathogenesis 56. In cardiac pathology, SYT17 functions downstream of the HERNA1-SMG1 axis in modulating stress-induced hypertrophy 1.