Syntaxin 3, like most SNAREs, is a type IV membrane protein with a relatively large N-terminus containing the SNARE motif located in the cytoplasmic side and a transmembrane domain located close to the C-terminus that functions as an anchor.nSyntaxin 3 functions as a plasma membrane protein t-SNARE that is involved in epithelial cell polarization. Indeed, Syntaxin 3 is specifically localized in the apical membrane of polarized epithelial cells where it likely has a role in the polarized trafficking of newly synthesized proteins
