Tsumura Yoshihiko, Suyama Yoshihisa
Bio-resources Technology Division, Forestry and Forest Products Research Institute, Kukizaki, Ibaraki, 305-8687, Japan.
Evolution. 1998 Aug;52(4):1031-1042. doi: 10.1111/j.1558-5646.1998.tb01831.x.
Mitochondrial DNA polymorphism of 40 populations of five Abies species was investigated using PCR-amplified coxI and coxIII gene probes. Using four combinations of probe and restriction enzyme, we detected three major haplotypes and 15 total haplotypes. We also found varied levels of gene diversity for the different species: 0.741, 0.604, 0.039, 0.000, and 0.292 for A. firma, A. homolepis, A. veitchii, A. mariesii, and A. sachalinensis, respectively. The marginal and southern populations of A. firma and A. homolepis have unique haplotypes, especially the Kyushu, Shikoku, and Kii Peninsula populations, which inhabit areas coinciding with probable refugia of the last glacial period and possess high levels of mtDNA genetic diversity. The haplotypes in some populations suggested mtDNA capture also occurred between species through introgression/hybridization. The strong mtDNA population differentiation in Abies is most likely due to the maternal inheritance of mitochondria and restricted seed dispersal. A phenetic tree based on the genetic similarity of the mtDNA suggests that some species are polyphyletic. Based on mtDNA variation, the five Abies species could be divided roughly into three groups: (1) A. firma and A. homolepis, (2) A. veitchii and A. sachalinensis, and (3) A. mariesii. However, we found that all these Abies species, except A. mariesii, are genetically very closely related according to an analysis of their cpDNA sequences. This showed that the chloroplast rbcL gene differed by only one base substitutions among the four species. We believe that the mtDNA variation and cpDNA similarity clearly reflect relationships among, and the dissemination processes affecting these Abies species since the last glacial period.
利用聚合酶链式反应（PCR）扩增的细胞色素氧化酶亚基I（coxI）和细胞色素氧化酶亚基III（coxIII）基因探针，对5种冷杉属植物40个种群的线粒体DNA多态性进行了研究。通过探针和限制性内切酶的四种组合，我们检测到三种主要单倍型和总共15种单倍型。我们还发现不同物种的基因多样性水平各异：日本冷杉、台湾冷杉、云杉冷杉、千岛冷杉和库页冷杉的基因多样性分别为0.741、0.604、0.039、0.000和0.292。日本冷杉和台湾冷杉的边缘种群和南部种群具有独特的单倍型，尤其是九州、四国和纪伊半岛的种群，它们栖息的区域与末次冰期可能的避难所重合，并且拥有高水平的线粒体DNA遗传多样性。一些种群中的单倍型表明，线粒体DNA捕获也通过渐渗/杂交在物种间发生。冷杉属中线粒体DNA种群分化强烈，最可能是由于线粒体的母系遗传和有限的种子传播。基于线粒体DNA遗传相似性的聚类树表明，一些物种是多系的。基于线粒体DNA变异，5种冷杉属植物大致可分为三组：（1）日本冷杉和台湾冷杉，（2）云杉冷杉和库页冷杉，（3）千岛冷杉。然而，根据叶绿体DNA序列分析，我们发现除千岛冷杉外，所有这些冷杉属物种在遗传上都非常密切相关。这表明，在这四个物种中，叶绿体rbcL基因仅相差一个碱基替换。我们认为，线粒体DNA变异和叶绿体DNA相似性清楚地反映了这些冷杉属物种自末次冰期以来的相互关系以及影响它们的传播过程。
