Constitutive Androstane Receptor

The constitutive androstane receptor (CAR, also known as nuclear receptor subfamily 1, group I, member 3, NR1I3) belongs to the nuclear receptor superfamily that exhibits enriched expression in the small intestine, liver, and gallbladder. CAR plays an important role in coordinating cellular responses to the stimulation of both exogenous and endogenous chemicals by regulating the expression of its target genes. CAR can be activated the classical direct ligand binding, such as bilirubin, steroids, and xenobiotics, via the ligand binding domain (LBD) or by a mutedly defined ligand-independent indirect mechanism. CAR plays a crucial role in the regulation of drug metabolism, energy homeostasis, and cancer development through modulating the transcription of its numerous target genes.