SREBF-1 is synthesized as inactive precursors in ER, where it resides in a complex with SCAP, a sterol sensor, and INSIG-1. Upon activation, when sterol levels are low, SCAP undergoes a conformational change and is released from INSIG. SCAP assists the transport of the precursor SREBF-1 to the Golgi apparatus followed by a two-step proteolytic cleavage thus releasing a transcriptionally active N-terminal domain. This domain is subsequently translocated to the nucleus, resulting in the expression of SREBF target genes.