甘蓝型油菜BnGS3和BnGhd7的同源克隆及其与油菜产量相关性状的关系

Homologous Cloning of BnGS3 and BnGhd7 Genes in Brassica napus and Their Relationship with Rapeseed Yield-related Traits

甘蓝型油菜为异源四倍体,基因组结构复杂,而水稻基因组与油菜基因组具有一定的共线性。本研究利用水稻产量相关基因GS3和Ghd7序列信息,通过同源克隆方法,获得了甘蓝型油菜的同源基因BnGS3和Bn Ghd7。BnGS3有6个外显子,ORF全长666 bp,编码222个氨基酸。BnGS3蛋白具有水稻GS3四个保守结构域中的VWF结构,属于A型。Bn Ghd7含有1个外显子,ORF全长1014 bp,编码337个氨基酸。Bn Ghd7蛋白具有N端的B-Box和C端的CCT两个重要的结构域。BnGS3和Bn Ghd7分别位于A2和A10连锁群,比较测序得到BnGS3的多态性标记brgs-16及Bn Ghd7的多态性标记brghd-3和ghd7-7,其中brghd-3与千粒重(P<0.05)、ghd7-7与株高(P<0.01)正相关,ghd7-7与开花期负相关(P<0.05)。上述结果表明,利用水稻功能基因序列信息克隆甘蓝型油菜的同源基因是可行的,为油菜功能基因研究提供了一种有效途径。

Brassica napus is an allotetraploid with complex genomic structure,but Brassica genome has a collinearity with that of rice.In this study,the homologous genes BnGS3 and BnGhd7 of Brassica napus were obtained by homologous cloning of the yield related genes GS3 and Ghd7 of rice.BnGS3 has six exons with a 666 bp of ORF and encodes 222 amino acids.BnGS3 protein has VWF structure,one of the four conserved domains of rice GS3,and belongs to type A.BnGhd7 contains one exon having ORF with a full-length of 1014 bp and encoding 337 amino acids.BnGhd7 protein has two important domains,the N-terminal B-Box and the C-terminal CCT.BnGS3 and BnGhd7 were located in linkage groups A2 and A10,respectively.Polymorphism markers brgs-16 of BnGS3 and polymorphism markers brghd-3 and ghd7-7 of BnGhd7 were obtained by comparative sequencing,among which brghd-3 with thousand kernel weight(P<0.05)and ghd7-7 with plant height(P<0.01)were positively correlated,and ghd7-7 was negatively correlated with flowering stage(P<0.05).The results indicate that it is feasible to clone the homologous genes of Brassica napus using rice functional gene sequence information,which provides an effective way in Brassica napus functional gene research.