LRAT (Lecithin Retinol Acyltransferase): LRAT is an enzyme that plays a key role in vitamin A metabolism by catalyzing the conversion of all-trans-retinol into all-trans-retinyl esters, the storage form of vitamin A. This process is essential for vision, immune function, and cellular differentiation. Deficiencies or mutations in LRAT can lead to retinal disorders and weakened immune responses, highlighting its importance in maintaining vitamin A balance and overall health.