The SREBP-SCAP complex is formed by the binding of sterol regulatory element binding protein (SREBP) by the SREBP-cleavage-activating protein (SCAP) in the ER membrane. SCAP escorts SREBP from the ER to the Golgi complex, where SREBP is cleaved to yield a transcription factor that translocates from the cytosol to the nucleus to regulate the transcription of genes encoding enzymes required for saturated fatty acid biosynthesis. Fly SREBP-SCAP complex-mediated ER to Golgi transport is inhibited by phosphatidylethanolamine, whereas in mammals it is regulated by sterols and polyunsaturated fatty acids. (Adapted from FBrf0147193.)