全基因组关联分析发掘紫苏种子油脂合成及调控的优异等位变异及关键基因

Perilla frutescens is a annual medical crop whose seed has the highest α-linolenic acid content among land plants. Identified the allelic variations and pivotal genes involving in seed oil biosynthesis and regulation of perilla is important for the genetic improvement of perilla and quality breeding of other oil crops. Previously we had sequenced and de novo assembled its genome, and had whole-genome re-sequencing of these samples for a complete map of genetic diversity form 200 perilla germplasms with extensive phenotypic diversity. In this project, we plan to carry out the following research: 1) 200 perilla germplasms were planted in three size, and quantative measurement of oil and fatty acid content in those perilla seeds. 2) Elucidation of the allelic variant underlying each specific metabolite by means of genome-wide association study (GWAS), then predicted possible molecular mechanism 3). Anticipated pivotal genes involving in seed oil biosynthesis and regulation and verified its function by genetic transformation or gene knockout. Anticipated yields from this project include an integrated map of Perilla genetic variations, the content and natural variation of oil-related metabolites across germplasms, and candidate (causal) variants for these agricultural phenotypes. This results will not only providing a sound basis for gene function characterization and marker-assisted molecular breeding of perilla, but also provide guidance for development of perilla germplasm resources and quality breeding of other oil crops.

紫苏是陆生植物种子油脂中α-亚麻酸含量最高的物种之一，研究并挖掘其合成与调控的优异等位变异及关键基因对紫苏遗传改良及对油料作物品质育种均具有重要意义。本项目基于课题组前期紫苏de novo基因组测序及核心群体200份样本重测序的研究结果，拟开展如下研究：1）群体样本在三个实验点平行种植，获得种子油脂含量及成分的表型数据。2）通过GWAS方法分析表型与基因型的相关性，以揭示与油脂合成与调控相关的优异等位变异。3）预测控制及调控紫苏种子油脂含量及成分的关键基因，并通过遗传转化或基因敲除进行功能验证。本课题预期将鉴定获得控制紫苏种子油脂合成与调控的优异等位变异及关键基因，并对其分子机制进行阐释。研究结果将为紫苏分子育种和遗传改良打下基础，并对紫苏种质资源的深入开发及油料作物品质育种具有重要的指导意义。

紫苏是a-亚麻酸含量最高的陆生植物。针对其种子含油量及a-亚麻酸含量等重要性状，本研究通过GWAS鉴定其关键变异位点并研究相关基因功能。具体研究内容包括：1）完成自然群体种植及种子成分检测及分析。2)组装两个高精度的紫苏基因组，通过倍性进化解析近代加倍事件下基因组的变化。通过重测序及GWAS分析，鉴定了影响种子含油量、a-亚麻酸含量及叶色形成等3个性状的关键变异并推测相关基因。3）通过对FAD基因家族鉴定及pfFAD3-1的功能研究，明确基因的催化活性。4）通过转录组及代谢组分析鉴定光诱导紫苏花青素形成的代谢通路合成酶及关键调控基因。项目研究意义主要包括：1）通过紫苏的基因组解析和关键性状的GWAS分析，为紫苏起源与进化路径，以及关键性状分子机制解析提供了重要的研究基础。2）紫苏FADs鉴定与功能研究为进一步解析紫苏a-高亚麻酸含量的分子机理和应用研究提供支持。3）光诱导紫苏花青素形成的研究，丰富了光调控下次生代谢产物合成调控机制，也为紫苏产业发展提供指导。.本项目已发表论文6篇，其中SCI文章4篇，1篇IF=14.6。撰写专著1本，认定2个植物新品种，获批2项行业标准。参加学术交流2人次。已全面完成项目指标。