Genetic basis of photopigment variations in human dichromats.
Genetic basis of photopigment variations in human dichromats.
复制标题
人类二色视者感光色素变异的遗传基础。
DOI：
10.1016/0042-6989(94)00306-8
复制
发表时间：
1995
期刊：
影响因子：
1.8
通讯作者：
Jacobs,GH
中科院分区：
文献类型：
--
作者：
Neitz,M;Neitz,J;Jacobs,GH
用视网膜电图研究了二色体中x编码色素的光谱灵敏度。这些受试者的作用光谱对应于四种明显不同的x编码视觉色素，两种不同的中波色素，光谱间隔为7 nm，两种不同的长波色素，光谱间隔为5 nm。氨基酸序列是通过检查编码色素的基因推断出来的。视蛋白结构和色素光谱的两两比较证实并澄清了先前的结论。基因外显子5的替换产生了光谱差异，将人类x编码色素分为中波和长波两类。外显子2-4的多态性产生属于这些主要类别的色素亚型。将中波基因的一半替换为长波序列（外显子1-3）不会改变中波谱。在230,233和180位置的组合取代在中波色素光谱中产生7nm的位移。长波色素的两种亚型在180位丝氨酸或丙氨酸的存在上有所不同，它们出现在二色视者、后异三色视者和正常色中，光谱上相隔5-7步。
The spectral sensitivities of the X-encoded pigments in dichromats were studied using the electroretinogram. The action spectra measured for these subjects correspond to four distinctly different X-encoded visual pigments, two different middle-wave pigments spectrally separated by 7 nm and two different long-wave pigments separated by 5 nm. Amino acid sequences were deduced from examination of the genes encoding the pigments. Pairwise comparisons of the opsin structures and pigment spectra confirm and clarify earlier conclusions. Substitutions in exon 5 of the genes produce the spectral difference that separates human X-encoded pigments into middle- and long-wave classes. Polymorphisms in exons 2–4 produce subtypes of pigments that fall within those major classes. Substitution of half of a middle-wave gene with long-wave sequence (exons 1–3) does not shift the middle-wave spectrum. Combined substitutions at positions 230, 233 and 180 produce a 7 nm shift in the middle-wave pigment spectrum. Two subtypes of long-wave pigments that differ in the presence of serine or alanine at position 180 and occur in dichromats, deuteranomalous trichromats, and color normals are spectrally separated by 5–7 run.