CIDE_N domain of FSP27 proteins. The CIDE-N (cell death-inducing DFF45-like effector, N-terminal) domain is found in the FSP27/CIDE-C protein, which has been identified as a n adipocyte lipid droplet protein that negatively regulates lipolysis and promotes triglyceride accumulation. The CIDE protein family includes 3 members: CIDE-A, CIDE-B, and FSP27(CIDE-C). Based on sequence similarity with DFF40 and DFF45, CIDE proteins were initially characterized as mitochondrial activators of apoptosis. The CIDE-N domain of FSP27 is sufficient to increase apoptosis in vitro when overexpressed.