Involved in the secretory pathway (PubMed:15919093). Essential for membrane fusion mediated by either SYP41 or SYP61; triggers the fusion of phospholipid vesicles containing SYP41 or SYP61 and VTI12 (PubMed:15919093, PubMed:24021022). Interacts with SYP41 (PubMed:15919093). Core constituent of the SNARE complex required for membrane fusion at the trans-Golgi network (PubMed:15919093). Belongs to the synaptobrevin family.