FLI 06 (Axon 2277) is an inhibitor of endoplasmic reticulum (ER) export. This compound has the unique property to inhibit cargo recruitment to ER exit sites (ERESs): it disrupts the Golgi apparatus in a manner distinct from that of brefeldin A and golgicide A. FLI-06 inhibits general secretion at a step before exit from the endoplasmic reticulum (ER), which is accompanied by a tubule-to-sheet morphological transition of the ER, rendering it the first small molecule acting at such an early stage in secretory traffic. As such, it effectuates the accumulation of NotchΔE-eGFP in intracellular membranes[1].