ISOMERIZATION OF ALL-TRANS-RETINOIDS TO 11-CIS-RETINOIDS INVITRO
ISOMERIZATION OF ALL-TRANS-RETINOIDS TO 11-CIS-RETINOIDS INVITRO
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DOI：
10.1073/pnas.84.7.1849
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发表时间：
1987-04-01
影响因子：
11.1
通讯作者：
RANDO, RR
中科院分区：
文献类型：
--
作者：
BERNSTEIN, PS;LAW, WC;RANDO, RR
视紫红质再生所需的脊椎动物视觉循环的关键生化过程，即从全反式类维生素A产生11-顺式类维生素A，已被证明发生在体外。 A 600次。 g 青蛙视网膜/色素上皮匀浆上清液以时间依赖性方式将添加的全反式-[3H]视黄醇转化为 11-顺式-视黄醇、11-顺式-视黄醛和 11-顺式-视黄醇棕榈酸酯的混合物。 13-顺式-类维生素A仅通过非特异性过程形成少量。使用 600 次的洗涤颗粒部分进行研究。 g上清液表明全反式-[3H]视黄醇比全反式-[3H]视黄醛或全反式-[3H]视黄醇棕榈酸酯更有效地异构化为11-顺式-类视黄醇。 11-顺式-类视黄醇生物合成活性不耐热，可通过高速离心沉淀，并且主要存在于色素上皮而不是神经视网膜中。
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 .times. 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 .times. 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.