【摘要】 神经视蛋白(Neuropsin,OPN5)是非视觉成像蛋白的重要成员之一,主要分布于动物的眼睛、脊髓、大脑和睾丸中,是动物感光物质的重要组成成分.文章以黑线仓鼠(Cricetulus barabensis)为动物材料,利用RT-PCR技术克隆得到黑线仓鼠OPN5基因的cDNA序列1340bp(KY949483).生物信息学分析表明,该序列包括一个完整的开放阅读框架1134bp,部分5’端非翻译区和部分3’端非翻译区;序列G+C含量远高于A+T含量,提示其Tm值较高,热稳定性强;编码377个氨基酸;蛋白质序列组成、跨膜区和疏水性分析、信号肽分析等均表明,OPN5序列包含N端胞外区、跨膜域和C端胞内域,整体疏水性较强,没有信号肽,不属于分泌蛋白,这些特征均与OPN5膜蛋白的属性相符;OPN5包括7个跨膜拓扑结构、一个G蛋白偶联受体家族和一个视黄醛结合位点,第7个跨膜结构的赖氨酸残基与OPN5对紫外光的敏感性有关;同源性对比显示,黑线仓鼠与中国仓鼠(Cricetulus griseus)、金仓鼠(Mesocricetusauratus)、小鼠(Mus musculus)亲缘关系较近,而与灵长类、偶蹄类的物种亲缘关系均较远,这与传统的物种分类相一致,证实所克隆到的序列正确,同时提示OPN5进化的保守性.本研究为探究OPN5视蛋白在动物繁殖调控中的作用奠定了基础,具有重要理论的意义.更多还原

【Abstract】 Opsin is one important member of non-visual opsin which mainly distributed in the animal’s eyes,spinal cord,brain and testis and it is an important component of photographic material in animals.Based on the striped hamsters(Cricetulus barabensis)for materials,the cDNA sequence of OPN5 is cloned by RT-PCR.The sequence is 1340 bp in length,containing part of the 5’ noncoding region,part of the 3’noncoding region and a complete open reading frame of 1134 bpwhich encodes a polypeptide of 377 amino acids residues(KY949483).The content of G+C is higher than A+T in the sequence,indicating that its Tm value is higher and the thermal stability is strong.The analysis of amino acids composition,transmembrane region and hydrophobicity suggests that OPN5 contains N-terminal the extracellular region,transmembrane domain and the C-terminal intracellularregionand the whole hydrophobicity is strong.The signal peptide analysis shows OPN5 is not secreted proteins due to the lack of signal peptide.All these characteristics are consistent with the properties of the OPN5 as membrane protein.Sequence analysis showed that OPN5 consists of 7 transmembrane topology,one visual pigment(opsin)retinal binding site is underlined,one G-protein coupled receptors family and there is a Lysine residues on the 7 th trans-membrane structure of the OPN5 which is sensitive to ultraviolet light.The analysis of phylogenetic relationship showed the C.barabensis has a close relationship with C.griseus,Mesocricetusauratus and Mus musculus,while it is far from the primate and artiodactyla.These results isconsistent with the traditional classification of species,which suggesting the conservation of OPN5.This study plays a very important role in exploring the role of OPN5 about animal reproduction.更多还原