STX3 (syntaxin 3) is a SNARE protein that functions as a regulator of membrane fusion and gene expression 1. It mediates vesicle docking and fusion processes critical for polarized protein trafficking and secretory autophagy, where autophagosomes fuse with the plasma membrane to secrete cytosolic proteins including inflammatory mediators 2. STX3 localizes to the apical plasma membrane and functions in positive regulation of cell adhesion, protein localization to cell surfaces, and cell population proliferation [GO annotations]. Functionally, STX3 is linked with MYO5B and STXBP2, sharing a common disease mechanism in congenital diarrheal disorders 3. Mutations in STX3 cause microvillus inclusion disease (MVID), a rare autosomal recessive condition characterized by severe chr11 diarrhea, nutrient malabsorption, and failure to thrive, with some patients exhibiting extragastrointestinal manifestations 14. STX3 variants have also been associated with retinal dystrophy and retinal dystrophy with microvillus inclusion disease 4. Additionally, elevated STX3 expression correlates with poor prognosis in esophageal squamous cell carcinoma, suggesting potential oncogenic roles in non-gastrointestinal malignancies 5. STX3 may also link to immune responses, showing inverse expression patterns with IL36G in psoriasis-associated pathways 6.