EXOC4 (exocyst complex component 4) is a core component of the exocyst complex that mediates docking of exocytic vesicles with the plasma membrane 1. Beyond its canonical vesicle trafficking role, EXOC4 has emerged as a multifunctional protein with broader biological significance. In the immune system, EXOC4 stabilizes STING1 by suppressing K27-linked ubiquitination, thereby enhancing type I interferon signaling and antiviral immunity; mice with conditional Exoc4 deletion show increased susceptibility to herpes simplex virus infection 2. In cancer biology, EXOC4 promotes diffuse-type gastric cancer metastasis by activating FAK signaling through modulation of integrin and EGF secretion, with high EXOC4 expression correlating with poor prognosis 3. EXOC4 dysfunction has clinical relevance in multiple disease contexts: altered EXOC4 methylation is associated with worse neurological outcomes following ischemic stroke, potentially through modulation of endocytosis and natural killer cell activation 4. Rare heterozygous deletions cause nephrotic syndrome and podocyte dysfunction by disrupting slit diaphragm protein trafficking 1. Additionally, EXOC4 variants associate with type 2 diabetes risk 5, peripheral axonopathies 6, and schizophrenia-related phenotypes including synaptic dysfunction and delusions 78.