生物多样性

• •    

多基因联合揭示海南鲌的遗传结构与遗传多样性

向登高1,2,李跃飞2,李新辉2,陈蔚涛2*,马秀慧1*   

  1. 1. 贵州大学动物科学学院,贵阳550025;2. 中国水产科学研究院珠江水产研究所,广州 510380
  • 收稿日期:2021-04-29 修回日期:2021-06-01 出版日期:2021-07-27 发布日期:2021-07-27
  • 通讯作者: 陈蔚涛

Population structure and genetic diversity of Culter recurviceps are revealed by multi-loci

Denggao Xiang1,2, Yuefei Li2, Xinhui Li2, Weitao Chen2*,Xiuhui Ma1*   

  1. 1 College of Animal Science, Guizhou University, Guiyang 2 Pearl River Fisheries Research Institute, Chinese Academy of Fishery Science, Guangzhou 510380
  • Received:2021-04-29 Revised:2021-06-01 Online:2021-07-27 Published:2021-07-27
  • Contact: Weitao Chen

摘要: 海南鲌(Culter recurviceps)是我国华南地区重要经济鱼类,但是由于受到近些年水利开发、过渡捕捞、环境污染等诸多因素的影响,海南鲌的资源量快速下降,亟需得到更多的关注和保护。群体遗传学不仅可以揭示特定物种的遗传多样性和遗传结构,还能为被被研究物种的管理和保护提供重要的建议。本研究的主要目的是揭示海南鲌的遗传结构和遗传多样性,同时为其种质资源的保护和合理开发提供重要科学参考。本研究采集了华南地区23个地理群体207尾海南鲌样本,测定了2个线粒体基因(CytbND2)和从Barcode of Life Data System数据库获得相对应线粒体COI基因,并联合三个基因和多种分析方法(系统发育分析、分化时间估算、单倍型网状图、群体遗传分析和Mantel检验)对海南鲌的遗传结构和遗传多样性展开研究。系统发育分析和单倍型网状图表明华南地区海南鲌群体被分成3个谱系(I、II和III),其中谱系 I和III由珠江的群体组成,谱系II由海南岛的群体组成。分化时间估算发现三个谱系之间的分化时间介于0.028–0.251Ma之间,暗示华南地区更新世气候变化可能是造成海南鲌谱系分化的重要原因。群体遗传分析发现海南鲌群体之间存在显著的遗传分化(FST = 0.511,P < 0.001),并且符合距离隔离模式(R = 0.348,P = 0.0010);种群动态历史分析,海南鲌群体可能在0.010–0.025 Ma经历了种群扩张,表明更新世的气候波动也影响了海南鲌的种群大小和分布。综上所述,海南鲌群体由三个谱系组成,更新世气候变化是导致三个谱系分化和影响海南鲌群体动态历史的重要因素。此外,海南鲌群体之间的遗传分化也可能受到了空间距离的影响。研究结果将为海南鲌的管理和保护提供重要科学数据。

关键词: 海南鲌, 遗传结构, 遗传多样性, 多基因

Abstract

Aim: Culter recurviceps (Cypriniformes: Cyprinidae) is an economic fish species in South China. Nevertheless, the resources of this species decline rapidly during recent years due to multiple factors such as water conservancy, overfishing, and environmental pollution. Therefore, more attention and conservation measure are needed for this species. Population genetic analyses can both reveal genetic diversity and population structure of particular taxon and provide implications for managing and protecting analyzed taxon. This aims of this study were to investigate the population genetic structure and genetic diversity of C. recurviceps and further provide important implications for the preservation and reasonable development of its resources.

Methods: In this study, we collected 207 individuals from 23 populations in the drainages in Southern China. With respect to the 207 individuals, two mitochondrial genes (Cytb and ND2) were sequenced and the corresponding mitochondrial COI genes were obtained from the Barcode of Life Data System (BOLD) database. We then combined the three genes to study the genetic structure and genetic diversity of C. recurviceps populations. Multiple analyses including phylogenetic analysis, divergence time estimates, haplotype network, population genetic analyses and Mantel tests were employed.

Results: Phylogenetic analysis and haplotype network revealed that C. recurviceps populations comprised three lineages (I, II and III). The members of lineages I and III contained populations from the Pearl River and the representatives of lineage II comprised of populations from the Hainan Island. Divergence time estimates indicated the three lineages were split between 0.028 and 0.251 million years ago (Ma), suggesting that Pleistocene climate change may have triggered the divergence of the three lineages. Population genetic analyses showed significant genetic differentiation (FST = 0.511, P < 0.001) and isolation by distance pattern (R = 0.348, P = 0.0010) were observed among C. recurviceps populations. Demographic analyses revealed that C. recurviceps populations might experience population expansion during 0.010–0.025 Ma, implying that Pleistocene climatic fluctuations have influenced the population size and distribution of C.recurviceps populations.

Conclusion: This study observed that C. recurviceps populations in Southern China consisted of three mitochondrial lineages. Pleistocene climate changes have not only triggered the divergences of the three lineages, but also influenced the demographic history of C. recurviceps populations. Furthermore, spatial distance acted as a key factor that improved the population differentiation among C. recurviceps populations. Above all, our results provided important data for the management and protection of C. recurviceps.

Key words: Culter recurviceps, population structure, genetic diversity, multi-loci