Construction of gene-databank based on the analysis of genetic variation of populations of Quercus see. Prinus in Japan.

落叶阔叶林是日本重要的遗传资源。本研究旨在阐明日本栎属栎亚组四个种的遗传结构，它们是日本栎林的重要组成部分。本研究收集了550份Q. mongolica，80 Q. serrata，40 Q. aliena和35 Q.来自日本各地以及中国、韩国和俄罗斯的一些地方的dentata样品。同时采集了488个毛毛豆样品。我们确定了叶绿体DNA的5,000 bp区域的序列，并在栎属物种中发现了11种单倍型。所有物种在相同的位置具有共同的单倍型，表明物种之间发生了渐渗。这些单倍型在日本东北部和西南部分为两大类。在国外样品中发现的单倍型表明，在过去的冰期，东北部的人通过库页岛迁移，西南部的人通过朝鲜半岛迁移。这一发现表明，这两个群体经历了不同的适应过程。为了证实这一点，我们从代表性的单倍型中克隆了甲硫氨酸合成酶基因，发现了两个差异较大的基因α和β。我们测试了这些基因的中性，发现了一些证据，表明不同类型的自然选择对这些基因的作用取决于基因被发现的位置。

Broad leaf deciduous forest is important genetic resources in Japan. This study aimed at clarifying the genetic structure of four Japanese oak species belonging to the genus Quercus, subsection Prinus which are important componets of above mentioned forest. DMA materials and the data obtained in this study were integrated into a gene-data-bank to serve for utilizing genetic information.In this study we collected 550 Q. mongolica, 80 Q. serrata, 40 Q. aliena and 35 Q. dentata samples from all over Japan and some places in China, Korea, and Russia. We also collected 488 samples of Fagus crenata. We determined sequences of a total of 5,000 bp regions of chloroplast DNA and found 11 haplotypes in the Quercus species. All the species possessed common haplotypes at the same locations, suggesting introgression had occurred among the species. These haplotypes were devided into two main groups in the northeast and the southwest part of Japan. Haplotypes found in the foreign samples indicated that those in northeast migrated via Sakhalin and those in southwest migrated via the Korean Peninsula during the past glacial ages. This finding suggests that these two groups experienced different adaptive process. In order lo confirm this, we cloned methionine synthase gene from the representative haplolypes and found two largely differentiated genes, α and β. We tested neutrality of these genes and found some evidence that different type of natural selection had operated on these genes depend on the location where genes arc found.