Karyotype Differentiation in Newly Discovered Members of the Drosophila obscura Species Group from Yunnan,China  

中国云南果蝇属暗果蝇种组的核型分化(英文)

作　　者：高建军[1] 渡部英昭 张亚平[1] 青塚正志 

机构地区：[1]中国科学院昆明动物研究所 [2]北海道教育大学 [3]东京都立大学

出　　处：《Zoological Research》2004年第3期236-241,共6页动物学研究（英文）

基　　金：ThepresentstudywassupportedbytheNationalNaturalScienceFoundationofChina ( 3 0 0 2 10 0 4),ChineseAcademyofSci ences (KSCX2 -1-0 5 )andJapanSocietyforthePromotionofScience (No 12 3 75 0 0 2 )

摘　　要：We examined mitotic chromosomes of three newly found members of the Drosophila obscura species group,D.luguensis,D.dianensis and D.limingi from Yunnan and compared their karyotypes to those of respective related species.D.luguensis possessed a diploid number of 12 chromosomes,comprising 3 pairs of metacentrics (V-shaped),2 pairs of acrocentrics (rod-like) and 1 pair of micro-chromosomes (dot-like).Both the X and Y were metacentrics.D.dianensis and D.limingi possessed a diploid number of 10 chromosomes,comprising 1 pair of large V-shaped,1 pair of moderate-sized V-shaped,2 pairs of submetacentric (J-shaped) chromosomes,and 1 pairs of dot-like chromosomes,with their X chromosomes were J-shaped and Y chromosomes were short rod-like ones.Based upon the results of chromosomal comparisons,geographic information of the sinobscura subgroup,as well inter-specific phylogenetic relationship deduced elsewhere,D.luguensis was considered to retain an ancestral form of the karyotype within this subgroup.The present observations have also implied that D.sinobscura (2n=12:2V,1J,2R,1D) might have derived from a sub-lineage of a pre-“sinobscura-hubeiensis” lineage by pericentric inversion of moderate-sized metacentric autosomes and D.hubeiensis (2n=10:4V,1D) from another sub-lineage of the same lineage by centric fusion of 2 pairs of acrocentric autosomes.Similar chromosomal changes of centric fusion,centric fission and/or pericentric inversion might have occurred during the course of species divergences between D.dianensis and D.subsilvestris (2n=12:3V,2R,1D),an European member closely related to D.dianensis,and between D.limingi and D.tsukubaensis (2n=12:3V,2R,1D),an East Asian member near to D.limingi.观察了新近发现于我国云南的果蝇属暗果蝇种组 (Drosophilaobscuraspeciesgroup)种类D luguensis、D dianensis和D limingi的有丝分裂中期核型 ,并将 3个种的核型与各自的近缘种类进行了比较。D luguensis具 2n =12条染色体 ,包括 3对中央着丝粒 (V形 )染色体、 2对近端着丝粒 (棒状 )染色体以及 1对微小 (点状 )染色体。其中X和Y染色体均为中央着丝粒染色体。D dianensis和D limingi具 2n =10条染色体 ,包括 1对大的V形常染色体 ,1对小的V形常染色体 ,2对J形 (亚中着丝粒型 )常染色体和 1对点状染色体。其中X染色体为J形 ,Y染色体为短棒状。基于核型比较的结果以及D sinobscura亚组地理分布的资料 ,结合种间系统发育关系研究结果 ,认为D luguensis可能保留了该亚组祖先种类的核型。D sinobscura的核型(2n =12 :2V ,1J ,2R ,1D)可能由一个pre “sinobscura hubeiensis”谱系的一个分支通过臂间倒位演化而来 ,而D hubeiensis的核型 (2n =10 :4V ,1D)可能由该谱系的另一分支通过着丝粒融合 (2对近端着丝粒常染色体的融合 )而形成。推测在D dianensis和近缘欧洲种D subsilvestris (2n =12 :3V ,2R ,1D)间、D limingi和东亚近缘种D tsukubaensis (2n =12 :3V ,2R ,1D)间的物种分化过程中 ,可能有相似的染色?

关 键 词：Drosophila obscura species group Karyotype differentiation China 

分 类 号：Q963[生物学—昆虫学]