水稻、玉米和小麦产量共性性状的遗传网络解析

Rice, maize and wheat are the top three crops in China. High and stable yields of these three crops are the basis of food security in China. Grain number per ear, seed size and seed weight are three common key components of grain yield. In this project, based on the support by previous Major Research Plan of the National Natural Science Foundation of China, we call together the excellent research groups to explore the common and distinguishing molecular mechanism of grain yield-related traits in three crops. Firstly, we will deeply investigate the functions and clarify the molecular regulatory mechanism of 9 nominated genes controlling grain number per ear, seed size and seed weight in three crops, containing FZP, SPP3, COG1 and APY2 in rice, KRN2, EL3 and KWL7 in maize, and MADS5 and TOC1 in wheat. Subsequently, we will validate the function and molecular regulatory mechanism of 9 target genes in the other two crops, and construct the genetic regulatory network of yield formation in three crops. Based on these information, we will explore the common and distinguishing character in the function of the studied genes and the genetic regulatory network of yield formation among three crops. Finally, we will elucidate the molecular basis of the 9 target genes during crop domestication and improvement. These results will not only provide novel target genes for the improvement of crop yield, but also lay a theoretical foundation to deeply understand the genetic basis of complex traits during crop domestication and improvement.

水稻、玉米和小麦是我国主要农作物，这三大作物的高产和稳产是保证我国粮食安全的基础。穗粒数、籽粒大小和粒重是三大作物产量的共有性状。本项目在前期重大研究计划支持的基础之上，集中优势力量，着重寻找三大作物影响产量性状的共性和特性机制，拟对有明确功能的控制作物产量或构成因子的9个基因（水稻：FZP, SPP3, COG1, APY2；玉米：KRN2, EL3, KWL7；小麦：MADS5, TOC1）进行深入分析，解析其调控产量性状形成的分子调控途径；并分别验证目标基因在其它两种作物中的功能和作用机制，最终构建三大作物产量性状形成的遗传调控网络，明确共性与特性。同时，利用基因组学、群体遗传学等方法解析这些基因共性演化的分子基础。本研究将为作物产量遗传改良提供新的靶基因，也为作物复杂性状的遗传结构和共性演化机制奠定理论基础。

水稻、玉米和小麦是我国三大主要的农作物。穗粒数、籽粒大小和粒重是三大作物共有的产量相关性状。本项目水稻中FZP、SPP3、COG1、APY2，玉米中KRN2、 EL3、KWL7，以及小麦中MADS5、TOC1等9个基因在三个作物中调控穗粒数、籽粒大小、粒重等关键产量性状的生物学功能和分子作用机制展开了研究，探明其在水稻、玉米、小麦三大作物间的共性与特性。. 克隆并解析了水稻FZP、SPP3、COG1、PAY2和LOG6/MAPK6调控穗型或粒形的分子机制；验证了玉米KRN2和EL3的同源基因OsKRN2和OsEL3在水稻中功能，发现OsEL3参与调控水稻的穗型和粒型；验证了小麦TOC1在水稻中的功能；验证了小麦MADS5的同源基因OsMADS17的功能，明确了OsMADS17具有调控水稻穗型和粒型的功能。.在全基因组水平上解析了玉米和水稻趋同选择的遗传基础；克隆了玉米穗行数关键基因KRN2基因，并发现其在玉米和水稻功能保守，在玉米和水稻驯化和改良过程中经历了趋同选择；克隆了玉米穗长关键基因EL3基因，发现其在玉米和小麦功能保守；对FZP、SPP3、COG1、PAY2、MADS5等水稻或小麦提名基因，在玉米中获得了转基因材料，相关表型正在鉴定中；系统解析了玉蜀黍各亚种间的进化关系，并在全基因组解析了玉米驯化和适应性的遗传基础；剖析了玉米重要农艺性状在玉米-大刍草群体中的遗传基础，为玉米产量相关基因的克隆奠定了基础。. 解析了小麦控制粒重的基因MADS5的生物学功能和分子调控途径；解析了水稻基因FZP、PAY2，玉米基因KRN2和EL3在小麦中同源基因的生物学功能和分子调控途径。. 构建了三大作物穗粒数、粒重等产量性状建成的遗传调控网络，并挖掘了这些调控网络在三大作物中的共性与个性。本研究为作物产量遗传改良提供新的靶基因，也为作物复杂性状的遗传结构和共性演化机制奠定了理论基础。