SNARE involved in targeting and fusion of ER-derived transport vesicles with the Golgi complex as well as Golgi-derived retrograde transport vesicles with the ER.
Subcellular locations: Endoplasmic reticulum membrane, Endoplasmic reticulum-Golgi intermediate compartment membrane, Golgi apparatus, Cis-Golgi network membrane, Golgi apparatus, Trans-Golgi network membrane, Melanosome
Concentrated most in the intermediate compartment/cis-Golgi network and the cis-Golgi cisternae 1 and 2. Greatly reduced in concentration at the trans end of the Golgi apparatus.