Cyp27c1 Red-Shifts the Spectral Sensitivity of Photoreceptors by Converting Vitamin A1 into A2.
Cyp27c1 Red-Shifts the Spectral Sensitivity of Photoreceptors by Converting Vitamin A1 into A2.
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Cyp27c1 通过将维生素 A1 转化为 A2 来红移光感受器的光谱敏感性。
DOI：
10.1016/j.cub.2015.10.018
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发表时间：
2015-12-07
期刊：
影响因子：
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通讯作者：
Corbo JC
中科院分区：
文献类型：
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作者：
Enright JM;Toomey MB;Sato SY;Temple SE;Allen JR;Fujiwara R;Kramlinger VM;Nagy LD;Johnson KM;Xiao Y;How MJ;Johnson SL;Roberts NW;Kefalov VJ;Guengerich FP;Corbo JC
有些脊椎动物已经进化出超出人类视觉范围的视觉灵敏度。提高对长波光敏感性的一种机制是用11-顺式3,4-二脱氢视网膜取代光色素中的11-顺式视网膜发色团。尽管对这一主题进行了一个多世纪的研究，但这种感知开关的酶基础仍然未知。在这里，我们发现细胞色素P450家族成员Cyp27c1通过将维生素A1（11-顺式视网膜的前体）转化为维生素A2（11-顺式3,4-二脱氢视网膜的前体）来调节这种开关。敲除斑马鱼体内的cyp27c1基因会破坏维生素A2的产生，使斑马鱼的光感受器的光谱灵敏度丧失红移能力，并降低其对近红外光的观察和反应能力。因此，单个酶的表达通过控制眼睛中维生素A1和A2的平衡来调节整个视觉系统的动态光谱调节。
Some vertebrate species have evolved means of extending their visual sensitivity beyond the range of human vision. One mechanism of enhancing sensitivity to long-wavelength light is to replace the 11-cis retinal chromophore in photopigments with 11-cis 3,4-didehydroretinal. Despite over a century of research on this topic, the enzymatic basis of this perceptual switch remains unknown. Here, we show that a cytochrome P450 family member, Cyp27c1, mediates this switch by converting vitamin A1 (the precursor of 11-cis retinal) into vitamin A2 (the precursor of 11-cis 3,4-didehydroretinal). Knockout of cyp27c1 in zebrafish abrogates production of vitamin A2, eliminating the animal's ability to red-shift its photoreceptor spectral sensitivity, and reducing its ability to see and respond to near-infrared light. Thus, the expression of a single enzyme mediates dynamic spectral tuning of the entire visual system by controlling the balance of vitamin A1 and A2 in the eye.