Beta,beta-carotene 15,15'-dioxygenase 1 (BCO1) (BCO1)

Beta,beta-carotene 15,15'-dioxygenase 1 (BCO1) is a pivotal cytosolic enzyme in mammalian vitamin A metabolism, responsible for the symmetrical oxidative cleavage of provitamin A carotenoids, such as beta-carotene, into two molecules of retinaldehyde (retinal) (Source 2.3.2, 2.5.4). This reaction is the primary endogenous source of vitamin A, which is essential for critical biological processes including vision, immune function, and embryonic development (Source 2.5.4). BCO1 is highly expressed in the small intestine, liver, and retinal pigment epithelium, and its activity is dependent on a non-heme iron cofactor (Source 2.3.2, 2.4.4). Genetic polymorphisms in the BCO1 gene, notably R267S and A379V, are associated with significantly reduced enzyme activity, leading to inter-individual differences in carotenoid conversion efficiency and vitamin A status (Source 2.5.1, 3.2.2). Beyond its nutritional role, BCO1 has been identified as a therapeutic target in cardiovascular disease, where it modulates cholesterol levels and atherosclerosis resolution, and in oncology, particularly neuroblastoma, where it may influence cancer cell differentiation (Source 2.4.1, 3.1.1). Pharmacological modulation of BCO1 includes inhibition by synthetic retinoids like fenretinide and transcriptional suppression by glucocorticoids such as dexamethasone, highlighting its significance in metabolic regulation and drug-nutrient interactions (Source 3.3.1, 3.3.2).

Other names

Beta-carotene 15,15'-monooxygenaseBeta-carotene oxygenase 1BCMO1BCDO1BCO

Inhibition of enzyme activity (e.g., by fenretinide), transcriptional suppression of gene expression (e.g., by dexamethasone via PPARα), and competitive substrate interaction (e.g., by various carotenoids) (Source 3.3.1, 3.3.2).