以甘蓝型油菜新型恢复系NR1与不育系杂交后代可育植株幼小花蕾为材料,采用SMART（switching mechanism at 5′end of RNA transcript）技术构建了其全长cDNA文库.原始文库的滴度为5.2×107pfu/mL,重组率达96%.随机挑取21个噬菌斑,利用PCR扩增插入片段,电泳结果显示其长度集中在0.7~2 kb之间,平均大小约为1.1 kb.采用铺平板法扩增文库,扩增后的文库滴度为4.3×1012pfu/mL.结果表明,所构建的文库达到了用于分离目的基因的建库要求,为后续恢复基因等重要功能基因全长cDNA的分离克隆奠定了基础.
Thirty-two C-genome specific candidate bacterial artificial chromosome （BAC） clones were successfully screened from the BAC library by four-dimensional PCR method with the primer pairs of 75 simple sequence repeat （SSR） markers located in the nine C-genome linkage groups of Brassica napus. The screened 32 BAC clones have an average insert size of 114.2 kb with a range of 30–190 kb. They are the first set of C-genome BAC clones screened from B. napus genomic BAC library. The average insert size of this set of BAC clones presented that the constructed BAC library had a high quality. This set of BAC clones can be used as markers to identify individual chromosomes of B. napus C-genome.
YAN XiaohongYUAN YabinZHAO XueyaZHA MinminDAI ShuangLIU FengWANG YuantaoWEI Wenhui
AINTEGUMENTA （ANT） gene has been proved to have a novel function on controlling the organ size and the seed weight in Arabidopsis thaliana, the research on its orthologous gene in Brassica napus will be of potential interest to elucidate the molecular mechanism of rapeseed development and increase the rapeseed output. A SMART cDNA library of the flower bud from B. napus cultivar Zhongshuang 9 was constructed, and the full-length cDNAs of two homologous BnaANT candidate genes were cloned by PCR in B. napus, namely BnaX.ANT.a （GenBank accession no. DQ211969） and BnaX.ANT.b （accession no. DQ211970）. They shared 87.1 and 83.4% amino acid identity with ANT of A. thaliana, respectively. There is 87.4% amino acid identity between BnaX.ANT.a and BnaX.ANT.b. By quantitative real-time PCR, the obviously differential expression levels of the two BnaANT candidate genes were detected in the 28 DAF seeds of the big and small grains B. napus lines, the expression abundance of BnaANT in the 28 DAF seed of 9311 was over three times compared to that of 9260, which indicates that these two BnaANT genes are also likely related to the floral organ size and the seed weight in B. napus.
