金色果蝇复合种(Drosophila auraria species complex)的分子系统学研究  

Molecular Phylogeny of Drosophila auraria Species Complex

作　　者：陆剑[1] 吕静[1] 陈慧贤[1] 张文霞[1] 戴灼华[1] 

机构地区：[1]北京大学生命科学学院,北京100871

出　　处：《Acta Genetica Sinica》2002年第1期39-49,共11页

基　　金：国家自然科学基金资助项目 (No . 30 0 5 0 0 0 1)~~

摘　　要：测定了金色果蝇复合种 (Drosophilaaurariaspeciescomplex)的 5个姊妹种 (D .auraria、D .biauraria、D .triaurar ia、D .quadraria和D .subauraria)及其近缘种D .rufa的ITS1片段和COⅡ基因的全序 ,以及Adh基因的部分序列。以D .rufa、D .melanogaster和D .yakuba为外群 ,分别用最大简约 (MP)法和邻接 (NJ)法根据每个分子标记的序列构建金色果蝇复合种系统发生树。在得到的 6棵系统树中 ,D .subauraria总位于系统树的基部。该复合种的ITS1、Adh和COⅡ的综合序列长度为 2 32 7bp(排除插入和缺失位点 ) ,能提供 2 5 5个简约信息位点。根据综合序列构建的系统树较好地揭示了 5个姊妹种间的系统发生关系 :D .subauraria在金色果蝇复合种内最早分支出来 ,随后发生了D .biauraria的分化 ,D .auraria、D .triauraria和D .quadraria之间的亲缘关系较近 ,形成的时间相对较晚。推测金色果蝇复合种的祖先种约在 2 33百万年前与D .rufa发生分歧 ,随后由暖温带侵入寒温带。在寒温带 ,D .subau raria约在 0 88百万年前与其他 4个姊妹种的祖先种发生了分歧 ,D .biauraria约在 0 31百万年前分化出来 ;而分布在较低纬度的D .auraria、D .triauraria和D .Drosophila auraria species complex consists of five sibling species D. auraria, D. biauraria, D. triauraria, D. quadraria and D. subauraria. The complete sequences of nuclear ITS1 (internal transcribed specer 1) and mitochondrial CO Ⅱ (Cytochrome Oxdase Ⅱ), and partial sequences of nuclear Adh (alcohol dehydrogenase) of these five sibling species and their closely related species, D. rufa , were determined. Using D. rufa, D. melanogaster and D. yukuba as outgroups, both most parsimony (MP) and neighbor joining (NJ) trees were constructed based on the sequences of each genetic marker. In each tree, D. subauraria always branched off first within Drosophila auraria species complex. Combined sequences of ITS1, Adh and CO Ⅱ are 2327bp (excluding gaps), of which 255 sites are parsimony informative. Phylogenetic analyses based on the combined data sets can resolve the phylogenetic relationships of the five sibling species relatively well. According to the MP and NJ trees based on the combined sequences, D. subauraria was the first toemerge within Drosophila auraria species complex, thereafter D. biauraria branched off, D. auraria, D. triauraria and D. quadraria had a relatively recent speciation history. In this paper we propose a hypothesis about divergence events in Drosophila auraria species complex: The ancestor of this spcies complex diverged with D. rufa in warm temperate regions about 2.33 myr ago, then they invaded into cold temperate regions. In cold temperate regions, D. subauraria was firstly derived from the ancestor of Drosophila auraria species complex about 0.88 myr ago, thereafter D. biauraria emerged about 0 31 myr ago. During the process the ancestor reinvading into warm temperate and subtropical regions, speciations of D. auraria, D. triauraria and D. quadraria were gradually completed. This hypothesis does not agree on the previous opinion that D. quadraria was the ancestral species of Dros

关 键 词：金色果蝇复合种 ITS1片段 Adh基因 COⅡ基因 系统发生 

分 类 号：Q969.462.2[生物学—昆虫学] Q963