基于线粒体细胞色素b基因序列的新安江流域温州光唇鱼群体遗传研究

Population Genetic Analyses of Acrossocheilus wenchowensis in Xin’an Basin Based on the Mitochondrial DNA Cytochrome b Gene

中文关键词: 新安江流域  温州光唇鱼  mtDNA Cyt b  群体遗传分析

英文关键词: Xin’an Basin  Acrossocheilus wenchowensis  mtDNA Cyt b  Population genetic analyses

中文摘要:

      为了解新安江流域温州光唇鱼(Acrossocheilus wenchowensis)的群体遗传变异规律，本研究采集6个不同地理群体共170个体，采用线粒体基因组细胞色素b(mtDNA Cyt b)测序方法，研究群体遗传结构以及群体变化的历史动态。研究显示，温州光唇鱼不同地理群体间的遗传多样性差异较大，整体遗传多样性水平较低。群体间检测到了不同程度的遗传分化，但由于分化时间较短(上新世晚期)，分子遗传变异主要来自于群体内。温州光唇鱼约于335万年前发生过群体扩张事件。群体扩张时，全球处于末次冰川时期的早期，群体的扩张并未受到低温的影响，因此，推测新安江流域可能是潜在的冰期避难所。祖籍地重建分析结果表明，新安江流域温州光唇鱼起源于率水上游和练江上游，经过一系列的群体扩散–隔绝–分化事件，形成现今的分布。原种的鉴定为新安江流域光唇鱼群体保育工作提供理论依据。

英文摘要:

      In order to clarify the variations in population genetic patterns of Acrossocheilus wenchowensis in the Xin’an Basin, 170 individuals from 6 different geographic populations were collected. Subsequent analyses of population genetic structure and historical demography were carried out using the mitochondrial DNA cytochrome b (mtDNA cyt b) gene. The results suggested that the genetic diversity of different geographic populations varied greatly, and that of A. wenchowensis was low. Whereas different levels of genetic differentiation were detected among the 6 populations, molecular genetic variation was mainly detected within populations owing to the short divergence time. Population expansion had occurred approximately 3.35 million years ago, while the global temperature was freezing. The expansion had not been affected by low temperatures. Therefore, the Xin’an Basin may have been a potential refuge during the glacial period. Reconstruction of the ancient area suggested that the Shuaishui and Lian rivers may have been the areas of A. wenchowensis origin in the Xin’an Basin. After population diffusion, isolation, and differentiation, the current distribution patterns emerged. The identification of the original population provides a theoretical basis for the conservation of A. wenchowensis in the Xin’an Basin.