Isomerization of all-trans-retinoids to 11-cis-retinoids in vitro.

作者：Paul S. Bernstein, W C Law, Robert R. Rando · 发表于：Proceedings of the National Academy of Sciences · 年份：1987 · DOI：10.1073/pnas.84.7.1849 · 被引用次数：184 · 研究领域：Retinal Development and Disorders、Photochromic and Fluorescence Chemistry、Photoreceptor and optogenetics research

The key biochemical process of the vertebrate visual cycle required for rhodopsin regeneration, 11-cis-retinoid production from all-trans-retinoids, is shown to occur in vitro. A 600 X g supernatant from a frog retina/pigment epithelium homogenate transforms added all-trans-[3H]retinol, in a time-dependent fashion, to a mixture of 11-cis-retinol, 11-cis-retinal, and 11-cis-retinyl palmitate. 13-cis-Retinoids are formed in only minor amounts by nonspecific processes. Studies using washed particulate fractions of the 600 X g supernatant indicate that all-trans-[3H]retinol is isomerized to 11-cis-retinoids much more effectively than is all-trans-[3H]retinal or all-trans-[3H]retinyl palmitate. The 11-cis-retinoid biosynthetic activity is heat-labile, sedimentable by high-speed centrifugation, and largely found in the pigment epithelium rather than in the neural retina.