与甘蓝型油菜重要经济性状有关的DNA克隆在拟南芥遗传图谱中的整合

Integration of DNA Clones Related to Important Economic Traits of Brassica napus onto Arabidopsis Genetic Map

拟南芥与油菜同属十字花科植物芸薹族 ,亲缘关系很近 ,基因组间的同源性很高。在用拟南芥EST克隆和油菜DNA克隆作探针定位了甘蓝型油菜一系列重要性状的基础上 ,对 2 5个与油菜雄性不育恢复基因、硼高效利用基因、抗菌核病QTL及油菜种间杂种营养优势相关联的克隆进行了测序 ,在拟南芥基因组数据库中寻找到与这 2 5个克隆高度同源的序列。根据这些高度同源序列在拟南芥染色体上的相应位置 ,将油菜DNA克隆整合到了拟南芥遗传图谱上 ,其中油菜硼高效基因BE1两侧的标记克降整合在拟南芥第一染色体长臂一个较小的区段内。以该目标区段内的拟南芥EST克隆PA2 4为探针对甘蓝型油菜基因组比较作图 ,将该克隆定位在油菜连锁图BE1两侧标记之间 。

Arbidopsis thaliana and Brassica oilcrops are closely related species in Brassicae, Cruciferae , and show highly homologous genomes. After a serial important agronomic characteristics of Brassica napus being mapped with probes from EST clones of Arabidopsis and DNA clones of rapeseed, DNA segment sequencing was performed with 25 clones which were found to be closely linked to the CMS restore gene, the boron efficiency gene ( BE1 ), the Sclerotinia resistant QTLs and the characteristic of interspecific biomass heterosis in rapeseed respectively. Highly homologous sequences were found in Arabidopsis genome by searching the relative databases. According to the position of homologous sequences on the chromosomes of Arabidopsis , the 25 clones were integrated into the genetic map of Arabidopsis . Two markers flanking BE1 in B. napus were integrated into a narrow region at the short arm of chromosome 1 of Arabidopsis . One of EST clones, pA24, from this region was used as a probe to map B. napus and consequently been integrated in a position between the two flanking markers of BE1 . This event increased the confident for one to map the important characteristics of cultured Brassica species via reciprocal comparative mapping between Arabidopsis and target Brassica crops