Spectral sensitivity of guppy visual pigments reconstituted in vitro to resolve association of opsins with cone cell types
Spectral sensitivity of guppy visual pigments reconstituted in vitro to resolve association of opsins with cone cell types
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DOI：
10.1016/j.visres.2016.06.013
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发表时间：
2016-10-01
期刊：
影响因子：
1.8
通讯作者：
Kawata, Masakado
中科院分区：
文献类型：
--
作者：
Kawamura, Shoji;Kasagi, Satoshi;Kawata, Masakado
孔雀鱼（Poecilia reticulate）的视网膜感光细胞，特别是对中长波长光敏感的感光细胞，具有显著的变异性。显微分光光度法（MSP）揭示了特立尼达和委内瑞拉（库马纳）孔雀鱼中不同的“绿色”、“绿黄色”和“黄色”视锥细胞。在孔雀鱼基因组中，有四个“长波”视蛋白基因座（LWS-1、LWS-2、LWS-3和LWS-4）。两个LWS-1等位基因具有潜在不同的光谱敏感性（LWS-1/180（Ser）和LWS-11180（Ala））。此外，还存在两个“中波”基因座（RH 2 -1和-2）、两个“短波”基因座（SWS 2-A和-B）、单个“紫外”基因座（SWS 1）以及单个“视紫红质”基因座（RH 1）。然而，这些色素的吸收光谱还没有被直接测量，并且细胞类型与这些视蛋白的关联仍然是推测性的。在本研究中，我们在体外重建这些视蛋白色素。最大吸光度的波长（λ（max））。分别为571 nm（LWS-//180（Ser））、562 nm（LWS-1/180（Ala））、519 nm（LWS-3）、516 nm（LWS-2）、516 nm（RH2-1）、476 nm（RH2-2）、438 nm（SWS2-A）、408 nm（SWS2-B）、353 nm（SWS1）和503 nm（RH1）。LWS-3的λ（max）比“五位点”规则预期的值（560 nm）短得多。两个LWS-1等位基因可以解释特立尼达和库马纳孔雀鱼黄锥类MSP λ（max）值的差异。在绿色剑尾鱼中没有短波位移的LWS-3和绿黄色锥体，这支持了这类孔雀鱼细胞共表达LWS-1和LWS-3的假设。这些结果揭示了孔雀鱼视觉系统变异的基础，并提供了深入了解这些热带鱼的行为和生态。(C)2016作者爱思唯尔有限公司出版
The guppy (Poecilia reticulate) shows remarkable variation of photoreceptor cells in the retina, especially those sensitive to middle-to-long wavelengths of light. Microspectrophotometry (MSP) has revealed varying "green", "green-yellow" and "yellow" cone cells among guppies in Trinidad and Venezuela (Cumana). In the guppy genome, there are four "long-wave" opsin loci (LWS-1,-2,-3 and -4). Two LWS-1 alleles have potentially differing spectral sensitivity (LWS-1/180(Ser) and LWS-11180(Ala)). In addition, two "middle-wave" loci (RH2-1 and -2), two "short-wave" loci (SWS2-A and -B), and a single "ultraviolet" locus (SWS1) as well as a single "rhodopsin" locus (RH1) are present. However, the absorption spectra of these photopigments have not been measured directly and the association of cell types with these opsins remains speculative. In the present study, we reconstituted these opsin photopigments in vitro. The wavelengths of maximal absorbance (lambda(max)).) were 571 nm (LWS-//180(Ser)), 562 nm (LWS-1/180(Ala)), 519 nm (LWS-3), 516 nm (LWS-2), 516 nm (RH2-1), 476 nm (RH2-2), 438 nm (SWS2-A), 408 nm (SWS2-B), 353 nm (SWS1) and 503 nm (RH1). The lambda(max) of LWS-3 is much shorter than the value expected (560 nm) from the "five-sites" rule. The two LWS-1 alleles could explain difference of the reported MSP lambda(max) values for the yellow cone class between Trinidad and Cumana guppies. Absence of the short-wave-shifted LWS-3 and the green-yellow cone in the green swordtail supports the hypothesis that this cell class of the guppy co-expresses the LWS-1 and LWS-3. These results reveal the basis of variability in the guppy visual system and provide insight into the behavior and ecology of these tropical fishes. (C) 2016 The Authors. Published by Elsevier Ltd.