苦荞脱壳关键基因的鉴定与分子调控机制研究

Tartary buckwheat (Fagopyrum tataricum) is a rare crop suitable for medicine and food due to containing a lot of bioactive substances. Shelling is an important character for buckwheat developing as the first procedure for processing, however, most tartary buckwheat species are hard to dehull. So far, the molecular regulation mechanism underlying tartary buckwheat shelling has not been investigated. In the preliminary work, shell crack mutants have been gained by EMS mutagenesis of the hard shelling variety of "heifeng 1", and the critical pericarp separation period has been identified using easy shelling variety of "miqiao 1" and hard shelling variety of "xiqiao 1" as materials and transcriptome sequencing has been carried. The project will be carried out using "heifeng 1" as material based on the preliminary work as following: 1) the critical period will be identified and transcriptome sequencing will be carried to screen out differentially expressed genes and build the coexpression network; 2) whole genome resequencing will be carried out to analyze the candidate mutagenic gene, and the critical regulation genes will be identified combing with the coexpression network; 3) the functions of the critical regulation genes will be investigated to construct the molecular regulation network for tartary buckwheat shelling in order to uncover systematically the molecular regulation mechanism underlying tartary buckwheat shelling. The research results will provide important theoretical evidence for breeding improvement of tartary buckwheat shelling character, which enriches the research theory of crop grain shelling, and it is of great significance for the industrial production of tartary buckwheat.

苦荞（Fagopyrum tataricum）富含多种生物活性物质，是罕有的药食两用作物。作为加工的首要工序，脱壳对苦荞产业发展至关重要，然而大多苦荞品种不易脱壳。目前关于苦荞脱壳的分子调控机理尚未见报道。前期工作对难脱壳品种“黑丰1号”进行了EMS诱变并获得稳定遗传的壳裂突变体；同时以易脱壳品种“米荞1号”和难脱壳品种“西荞1号”为试材，初步确定了苦荞果皮分离的关键时期并进行了转录组测序。本项目拟在此基础上以“黑丰1号”为试材开展研究：1）明确果皮分离的关键时期，进行转录组测序，筛选差异表达基因并构建共表达网络；2）基因组重测序分析候选致变基因，结合共表达网络鉴定苦荞脱壳的关键调控基因；3）对候选关键基因进行功能分析，构建苦荞脱壳的分子调控网络，系统揭示苦荞脱壳的分子调控机制。该项研究将为苦荞脱壳性状改良育种提供重要的理论依据，丰富作物籽粒脱壳研究的理论，对苦荞产业化发展具有重要意义。

苦荞（Fagopyrum tataricum）是一种非常重要的药食兼用作物，日益被人们重视。然而多数苦荞品种不易脱壳，严重制约了苦荞的加工利用。截止目前，苦荞脱壳的分子调控机理尚未见报道。本项目以‘黑丰1号’及其壳裂突变体为研究材料，主要开展了如下工作：（1）通过对苦荞各组织进行石蜡切片显微结构观察和苯丙烷类代谢化合物测定，确定木质素是脱壳的关键因素，然后对木质素合成的相关酶开展了活性测定；（2）参考‘黑丰1号’全基因组信息进行转录组数据分析，筛选出了苦荞脱壳相关的差异表达基因，对其开展了基因功能研究；（3）通过BSA性状定位结合KASP标记定位到与苦荞木质素合成密切相关的候选基因Ftp53，Ftp53过氧化物酶原核表达并纯化后，开展了酶活检测，发现其对愈创木基底物具有明显的氧化能力，而对紫丁香基底物不具备氧化能力，这表明Ftp53在G型木质素的生物合成中发挥着重要的作用。本项目的研究结果具有广阔的应用前景，可用于后期开展苦荞脱壳性状及品质改良育种，同时开发苦荞保健食品等，这将极大地推动苦荞的产业化发展。