Author response image 1. HEK293T cells, which do not express SNAP25, were transfected with HA-tagged SCGN (WT or R77H).

These proteins were subsequently purified through an HA binding resin. The purified proteins, immobilized on the resin were then incubated with cellular lysates of STC-1 cells (0.75mg of lysate offered), and SNAP25 binding was determined by immunoblotting. Three technical replicates of the IP were performed (top three panels on the left). Input from HEK293 cells are shown on the right. This experiment is representative of 3 independent iterations.