Predicted to enable SNAP receptor activity and SNARE binding activity. Predicted to be involved in protein transport; vesicle docking; and vesicle fusion. Predicted to act upstream of or within vesicle-mediated transport. Predicted to be located in membrane. Predicted to be part of SNARE complex. Predicted to be active in endomembrane system; plasma membrane; and postsynapse. Human ortholog(s) of this gene implicated in congenital diarrhea. Orthologous to human STX3 (syntaxin 3).