紫花菜花球紫色基因精细定位

Anthocyanins play important roles in preventing cancer, heart diseases, etc. Purple cauliflower has drawn considerable attention because of its high content of anthocyanins. Taking the advantage of the compliment of genome sequencing of Brassica oleracea, we will use a new method based on super-BSA and re-sequencing techololgy to map the genes respondible for the anthocyanin biosynthesis in cauliflower. A F2 population derived from the crossing between a purple line and a white line will be used in this research. DNA of F2 displaying the white phenotype are bulked and subjected to whole-genome sequencing followed by alignment to the reference sequence. A "sliding window" technology will be used to screen the re-sequencing data in order to analyze the heterzygosity in the whole genome. It is expected to fine-map the genes responsible for the purple coloration of cauliflower based on this method. Then gene functional analysis will be performed on candidates selected from the fine-mapped region by cloning and qPCR technologies . Furthermore, closely linking molecular markers of the purple trait will be developed based on the sequencing results of the parents. This research will lay foundation of revealing the molecular genetic mechanisms of the purple trait of cauliflower and breeding new cultivars of cauliflower containing high contents of anthocyanins.

花青苷类物质具有抗癌和预防心脏病等生理功效，紫花菜由于富含花青苷而受到人们的广泛关注。本项目将充分利用甘蓝基因组测序信息，采用构建"超级池"和重测序策略，实现对花青苷合成相关基因的快速精细定位。对紫花菜和白色花椰菜杂交构建的F2群体中白色植株进行混池重测序，通过"滑窗法"对超级池重测序数据各个染色体区域进行杂合度检测，定位纯合位点，从而对紫花菜紫色性状基因进行精细定位。对定位区域内候选基因进行克隆测序及定量PCR分析，进一步验证紫色性状相关基因。并根据双亲测序结果开发与紫色性状基因紧密连锁的分子标记。此项工作将为揭示花椰菜紫色性状的分子遗传机制和培育紫花菜新品种奠定基础。

花青苷类物质具有抗癌和预防心脏病等生理功效，紫色蔬菜由于富含花青苷而受到人们的广泛关注。根据拟南芥花青苷和黄酮醇苷生物合成基因在芸薹属蔬菜中系统鉴定了73个花青苷同源基因。花青苷和黄酮醇苷合成基因在白菜中发生了扩增。通过对95份芸薹属蔬菜材料花青苷和黄酮醇苷合成基因的表达谱以及代表性材料中主要结构基因qPCR分析发现，花青苷合成特异的后期结构基因主要在紫色材料中表达，绿色材料中花青苷合成负调控基因的表达水平更高。不同材料中花青苷和黄酮醇苷含量具有显著差异和积累特性。本项目进一步充分利用基因组测序信息，采用构建"超级池"和重测序策略，开发了针对超级次测序数据的快速高效分析工具，实现对花青苷合成基因的快速精细定位。利用超级池（SuperBSA）高通量重测序的方法成功将紫白菜紫色性状基因定位到A03染色体末端1.5Mb的区域，并进一步定位到了一个花青苷代谢基因及其变异，同时开发了目标基因相关分子标记。