Kawaguchi Riki, Yu Jiamei, Honda Jane, Hu Jane, Whitelegge Julian, Ping Peipei, Wiita Patrick, Bok Dean, Sun Hui
Department of Physiology, David Geffen School of Medicine at UCLA, 650 Charles E. Young Drive South, Los Angeles, CA 90095, USA.
Science. 2007 Feb 9;315(5813):820-5. doi: 10.1126/science.1136244. Epub 2007 Jan 25.
Vitamin A has diverse biological functions. It is transported in the blood as a complex with retinol binding protein (RBP), but the molecular mechanism by which vitamin A is absorbed by cells from the vitamin A-RBP complex is not clearly understood. We identified in bovine retinal pigment epithelium cells STRA6, a multitransmembrane domain protein, as a specific membrane receptor for RBP. STRA6 binds to RBP with high affinity and has robust vitamin A uptake activity from the vitamin A-RBP complex. It is widely expressed in embryonic development and in adult organ systems. The RBP receptor represents a major physiological mediator of cellular vitamin A uptake.
维生素A具有多种生物学功能。它在血液中作为与视黄醇结合蛋白（RBP）的复合物进行运输，但目前尚不清楚细胞从维生素A-RBP复合物中吸收维生素A的分子机制。我们在牛视网膜色素上皮细胞中鉴定出STRA6，一种多跨膜结构域蛋白，作为RBP的特异性膜受体。STRA6与RBP具有高亲和力结合，并具有从维生素A-RBP复合物中摄取维生素A的强大活性。它在胚胎发育和成年器官系统中广泛表达。RBP受体是细胞摄取维生素A的主要生理介质。
