We recovered the phylogenetic relationships among 23 species and subspecies of the highly special-ized grade schizothoracine fishes distributing at 36 geographical sites in the Tibetan Plateau and its surrounding regi...We recovered the phylogenetic relationships among 23 species and subspecies of the highly special-ized grade schizothoracine fishes distributing at 36 geographical sites in the Tibetan Plateau and its surrounding regions by analyzing sequences of cytochrome b genes. Furthermore, we estimated the possible divergent times among lineages based on a historical geological isolation event in the Tibetan Plateau. The molecular data revealed that the highly specialized grade schizothoracine fishes were not a monophyletic group, but were the same as genera Gymnocypris and Schizogypsis. Our results indi-cated that the molecular phylogenetic relationships apparently reflected their geographical and historical associations with drainages, namely species from the same and adjacent drainages clustered together and had close relationships. The divergence times of different lineages were well consistent with the rapid uplift phases of the Tibetan Plateau in the late Cenozoic, suggesting that the origin and evolution of schizothoracine fishes were strongly influenced by environment changes resulting from the upheaval of the Tibetan Plateau.展开更多
文摘对浙江瑞安、福建宁德、福建东张水库3个地理群体共31例香鱼(Plecoglossus altivelis)的线粒体细胞色素b(Cyt b)基因和线粒体D-loop区序列进行了PCR扩增、序列测定、核苷酸组成和多态性分析。Cytb基因中,A、T、C和G4种核苷酸的比例分别为19.72%、29.71%、32.25%和18.32%,A+T含量为49.43%,G+C含量为50.57%。D-loop区序列中,A、T、C和G4种核苷酸的比例分别为29.99%、29.29%、23.80%和16.92%,A+T含量为59.28%,G+C含量为40.72%。在长度为1141bp的Cytb基因序列中,仅存在1个变异位点,核苷酸多样性指数(π值)为0.00028,31个样本中仅出现两种单倍型;857 bp 长的D-loop区序列中,仅存在5个变异位点,核苷酸多样性指数(π值)为0.00199,仅出现5种单倍型。这表明闽浙地区香鱼的遗传多样性水平很低,应当加大对香鱼的保护力度。
基金Supported by the National Natural Science Foundation of China (Grant Nos. 30670287, 30471345 and 30200029)the Chinese Academy of Sciences (Grant No. KSCX2-SW-125)
文摘We recovered the phylogenetic relationships among 23 species and subspecies of the highly special-ized grade schizothoracine fishes distributing at 36 geographical sites in the Tibetan Plateau and its surrounding regions by analyzing sequences of cytochrome b genes. Furthermore, we estimated the possible divergent times among lineages based on a historical geological isolation event in the Tibetan Plateau. The molecular data revealed that the highly specialized grade schizothoracine fishes were not a monophyletic group, but were the same as genera Gymnocypris and Schizogypsis. Our results indi-cated that the molecular phylogenetic relationships apparently reflected their geographical and historical associations with drainages, namely species from the same and adjacent drainages clustered together and had close relationships. The divergence times of different lineages were well consistent with the rapid uplift phases of the Tibetan Plateau in the late Cenozoic, suggesting that the origin and evolution of schizothoracine fishes were strongly influenced by environment changes resulting from the upheaval of the Tibetan Plateau.
