CIDEB

CideB, also known as cell death-inducing DFF45-like effector B, is a protein encoded by the human CIDEB gene. It belongs to the CIDE family, which includes other members such as CIDEA and CIDEC. The CIDE proteins are associated with lipid droplet biology and, in some contexts, with apoptotic processes, reflecting a dual role in metabolism and cell turnover.

Functionally, CideB is involved in hepatic and adipose tissue lipid metabolism. It is believed to participate in the regulation of lipid droplet size and triglyceride storage, potentially by promoting lipid transfer or fusion between droplets. In the liver, CideB may influence the assembly and/or secretion of very-low-density lipoprotein (VLDL), linking its activity to systemic lipid levels. The precise mechanisms remain an active area of research, and CideB may also participate in cellular stress responses.

Expression of CideB is highest in liver and adipose tissues, with detectable levels in other organs. The protein localizes to cytosolic lipid droplets and associated endoplasmic reticulum membranes, consistent with a role in intracellular lipid handling and droplet dynamics.

Clinical and physiological relevance is mainly studied in model systems. Altered CideB expression or function has been linked to changes in hepatic triglyceride content and insulin sensitivity in experimental contexts, suggesting CideB as a regulator of lipid homeostasis and a potential target for metabolic interventions.

Structurally, CideB belongs to the DFF45-like effector family and contains conserved CIDE-N and CIDE-C domains. The protein is conserved across mammals and other vertebrates, reflecting its evolutionary importance in lipid metabolism.