Opsin is a fellow of the G protein-coupled receptors (GPCRs) superfamily. It can be divided into visual and non-visual opsin according to whether it is directly involved in visual imaging. Opsin plays an important role in visual image formation and the regulation of non-image forming functions such as circadian entrainment in the growth, development and evolution of fish. Crimson snapper belongs to Perciforme mainly found in the Indo-West Pacific and the South China Sea. It is one of the most influential economic fishes in the South China Sea. In order to study the existence and expression of opsin gene in Crimson snapper, we sequenced the genome and tissue sample transcriptome of Crimson snapper. In this study, 32 opsin genes were identified from the genome of Crimson snapper. The length of these genes ranged from 1061 bp to 86203 bp and were distributed on 15 different chromosomes. The analysis of opsin gene family of Crimson snapper showed that the sws2 had two extra copies as compared with that of Zebrafish. Domain and motif analysis revealed that all the 32 opsin genes have seven-(pass)-transmembrane domain receptors (7TM receptors) each, and the opsin family contained 10 common motifs. The expression level of opsin gene, confirmed by RT-qPCR, was analyzed by using nine tissues transcriptome databases of Crimson snapper. The results showed that almost all opsin genes were highly expressed in the retina and brain, except opn7a and opn7b which were expressed in intestine and red skin, and almost no expression in other tissues. Our results provide a comprehensive basic knowledge for the opsin gene family of Crimson snapper, which has significance for the study of the function of opsin in Lutjanidaes.

Opsin 是 G 蛋白偶联受体 (GPCR) 超家族的成员。根据是否直接参与视觉成像，可分为视觉视蛋白和非视觉视蛋白。视蛋白在视觉图像形成和非图像形成功能的调节中起着重要作用，例如鱼类生长、发育和进化中的昼夜节律夹带。红鲷属于鲈形目，主要分布于印度-西太平洋和南海。是南海最具影响力的经济鱼类之一。为了研究红鲷鱼视蛋白基因的存在和表达，我们对红鲷鱼的基因组和组织样本转录组进行了测序。在这项研究中，从 Crimson snapper 的基因组中鉴定了 32 个视蛋白基因。这些基因的长度从 1061 bp 到 86203 bp 不等，分布在 15 条不同的染色体上。红鲷鱼视蛋白基因家族分析表明，与斑马鱼相比，sws2有两个额外的副本。域和基序分析显示，所有 32 个视蛋白基因均具有 7 个（通过）跨膜域受体（7TM 受体），并且视蛋白家族包含 10 个常见基序。使用 Crimson snapper 的九个组织转录组数据库分析通过 RT-qPCR 确认的视蛋白基因的表达水平。结果表明，除opn7a和opn7b在肠和红皮中表达外，几乎所有视蛋白基因在视网膜和脑中均高表达，在其他组织中几乎不表达。我们的研究结果为Crimson snapper视蛋白基因家族提供了全面的基础知识，对研究黄鳍鲷视蛋白的功能具有重要意义。