基于线粒体DNA Cyt b研究城市化对上海金线侧褶蛙遗传结构的影响

城市化在全球范围内快速扩张,已经成为影响物种进化的重要力量。两栖动物的迁移能力较弱,城市化导致两栖类被完全或部分的隔离,丢失更多的遗传多样性。本研究对上海市的金线侧褶蛙(Pelophylax plancyi)的mtDNA Cyt b部分序列进行分析,共扩增出235条序列,获得61个单倍型。研究表明城市区域遗传多样性较低,上海市的金线侧褶蛙分化程度处于中低的水平(Max F_ST=0.296;Min F_ST=0.004),各种群之间遗传分化有限。黄浦江及其支流可能作为水上扩散通道,有助于基因交流,各城市公园之间的遗传分化差异并不显著;而长江阻碍了种群之间的交流,城市公园和郊区,以及岛屿种群之间的遗传分化显著。此外,单倍型网络和系统发育分析表明,上海的金线侧褶蛙并没有对应城市化程度形成相应的单系。

The Influence of Urbanization on the Genetic Structure of Pelophylax plancyi Based on mtDNA Cyt b in Shanghai

Urbanization spreading rapidly on a global scale is being recognized as a major force driving the evolution of species.Amphibians have weak migration ability,and urbanization has led to complete or partial isolation of amphibians and a loss of genetic diversity.In this study,we analyzed the partial sequence of mtDNA Cyt b of the gold-striped pond frog(Pelophylax plancyi)in Shanghai.A total of 235 sequences were amplified and 61 haplotypes were obtained.The genetic diversity of urban areas was low and the degree of differentiation of gold-striped pond frog was at medium to low levels(Max F_ST=0.296;Min F_ST=0.004).Genetic differentiation among various populations was limited.Amphibians may be influenced by dispersal across both Huangpu River and its tributaries,therefore,the genetic differentiation between urban parks is not significant.The Yangtze River appears to be the leading genetic barrier for Beijing gold-striped pond frog,and significant genetic differentiation was observed between island populations,urban parks,and suburban populations.In addition,the haplotype network and phylogenetic analysis showed that Beijing gold-striped pond frog did not form a corresponding monophyletic according to the degree of urbanization.