Molecular population-genetic studies on adaptive evolution of Drosophila population.

为了理解适应性进化的分子基础，我们进行了四个实验，得到了以下结果：1。我们已经报告说，有一个北到南的渐变的加性遗传变异的生存能力和过剩的南方人口一直保持基因型与环境的相互作用。为了获得分子基础，对小笠原（南部）和青森（北部）种群进行了Southern印迹分析。用Gpdh、Adn、Amy和Pu四种基因的四种酶切方法，对每个群体的43条第二染色体进行了分析。北方和南方群体之间的差异不显著，但南方群体中独特插入/缺失的数量显著大于北方群体。因此，插入/缺失可能是多基因存活的重要条件之一。2.在自然群体中检测到sn甘油-3-磷酸脱氢酶基因（Gpdh）的重复和三倍。前者在每个群体中都表现出多态性。后者仅在青森和小笠原种群中表现出多态性。3.利用以前在北卡罗来纳州罗利发现的In（2L）t年龄。在人群中，进行有益突变的搜索。在大约4000代以前，在这种倒位中检测到一些有益的突变，并且在携带In（2L）t的染色体中其频率增加到18%。4.估计了copia、copia样元件（17，6，412）、流浪汉和I__-元件的转位率，即脱出率和插入率。Copia和copia样元件在其非遗传条件下不与hogo元件的运动发生交叉运动，而且Yamaguchi和Mukai（1974）发现的突变因子是流浪汉元件。

To understand the molecular basis of adaptive evolution, four experiments were conducted and the following results were obtained: 1. We have reported that there is a north-to-south cline of additive genetic variance for viability and that the excess in the southern population has been maintained by genotype-environment interaction. To obtain the molecular basis, southern blot analysis was conducted for the Ogasawara (south) and Aomori (north) populations. Forty-three second chromosomes were analyzed for each population using four proves inclusing the Gpdh, Adn, Amy and Pu genes, with eight restriction enzymes. Significant difference was not detected between the northern and southern populations except the following; in the southern population, the number of unique insersion/deletions was significantly larger than that in the northern population. Thus, insertions/deletions may be one of the important condidates of viability polygenes. 2. Duplication and triplication of the sn glycerol-3-phosphate dehydrogenase gene (Gpdh) were detected in natural populations. The former were found to be polymorphic in every population tested. The latter were polymorphic only in the Aomori and Ogasawara populations. 3. Using the previous finding of the age of In(2L)t in the Raleigh, N.C. population, search for beneficial mutations was conducted. It was detected that some beneficial mutation occurred in this inversion about 4000 generations ago and that its frequency has increased to 18% in the In(2L)t-carrying chromosomes. 4. The transposition rates, both the exision and insertion rates, were estimated for copia, copia-like elements (17,6, 412), hobo and I__- elements. Copia and copia-like elements are not cross-mobilized with the movement of hogo elements under their dysgenic condition.Furthermore, it was found that the mutator factor of Yamaguchi and Mukai (1974) is hobo elements.