摘要
利用RT-PCR技术克隆了10种鲤形目Cypriniformes鱼类卵透明带蛋白(ZP2)基因的cDNA全长序列,并初步探讨了这些鱼类ZP2基因的重复结构域变异与产卵习性的相关性。序列分析表明,10种鲤形目鱼类ZP2基因cDNA序列长度差异较大(1254~1734 bp),其编码的氨基酸保守结构域集中在N端信号肽序列、三叶草结构域和ZP结构域,变异集中在N端重复结构域中,不同物种的重复单元和重复次数不同,其中产漂流性卵和产沉性卵鱼类的重复结构域不含重复单元或重复单元重复次数较少(2~5次),而产粘性卵鱼类的重复结构域中通常含有多次重复单元(7~19次)。同源性分析结果显示,在鲤形目鱼类中,团头鲂Megalobrama amblycephala与鳊Parabramis pekinensis的相似性最高(99.7%),斑马鱼Danio rerio和鲫Carassius auratus的相似性最低(71.2%)。系统进化分析显示,鲤形目鱼类的ZP2氨基酸序列聚为一个单系,其中斑马鱼单独聚为一支,位于系统树的基部位置,与其他鲤形目鱼类形成姐妹群。10种鲤形目鱼类ZP2蛋白的二级结构成分和三维结构均存在一定的差异。进化选择压力分析结果表明,ZP2基因在鲤形目鱼类中受到正向选择,可能对其功能产生影响。
The full-length cDNA sequences of ZP2 gene from 10 Cypriniformes zona pellucida(ZP)were cloned by RT-PCR,and then the relationship between variations of ZP2 repeat domain and spawning types of Cypriniformes was preliminarily explored.Sequence analysis showed that the length of ZP2 gene is variable(1254-1734 bp).The amino acid sequence of ZP2 mainly located in 3 conserved domains,including N-terminal signal peptide sequence,trefoil factor family domain,and ZP domain,and the variation sites mainly located in N-terminal repeat domain with different repeat units and repeat frequencies.Less repeat units(up to 5 times)were identified in the repeat domain of species spawning drifting-eggs and demersal eggs,while multiple repeat units(7-19 times)were identified in the species spawning sticky-eggs.Homology analysis indicated that Megalobrama amblycephala had the highest similarity of ZP2 gene with Parabramis pekinensis(99.7%),and the similarity between Danio rerio and Carassius auratus was the lowest(71.2%).Phylogenetic analysis revealed that all the ZP2 amino acid sequences of Cypriniformes could cluster into a monophyletic clade,and Danio rerio formed a monophyly at the basal position of the phylogenetic tree.There were some differences in both the secondary structure and three-dimensional structure of ZP2 protein among 10 species of Cypriniformes.The result of evolutionary selection pressure analysis further showed that ZP2 gene was subjected to positive selection pressure in Cypriniformes.
作者
陈沙
刘焕章
曹文宣
俞丹
CHEN Sha;LIU Huanzhang;CAO Wenxuan;YU Dan(Dalian Ocean University, Dalian, Liaoning Province 116023, China;The Key Laboratory of Aquatic Biodiversity and Conversation of Chinese Academy of Sciences, Institute of Hydrobiology, Wuhan 430072, China)
出处
《四川动物》
北大核心
2021年第3期241-253,共13页
Sichuan Journal of Zoology
基金
中国科学院战略性先导科技专项(B类)(XDB31000000)
中国长江三峡集团有限公司项目(201903144)
中国生物多样性监测与研究网络项目。
关键词
鲤形目
ZP2
克隆
序列分析
选择压力
Cypriniformes
ZP2
cloning
sequence analysis
selection pressure
