Here is the quote from the above diagram from Metabolic Regulation: A Human Perspective by Keith N. Frayn, regarding cholesterol regulation (emphasis added): “The full length SREBP protein is located in the ER. It is associated with the SREBP cleavage activating protein (SCAP), which “senses” the level of cholesterol, or related sterols, within the membrane of the ER. When the cholesterol content is low, the SCAP-SREBP complex migrates to the Golgi complex, where specific proteases cleave SREBP to release the N-terminal portion, “mature” SREBP. Mature SREBP moves to the nucleus where it binds to sterol response elements in the promoter