SHB1 regulates seed development in Arabidopsis

主要研究者：最小Ni提案编号：IOS-0919886提案标题：“SHB 1调节拟南芥种子发育“被子植物中的双受精导致二倍体胚和三倍体胚乳的形成。在拟南芥中，种子发育经历了胚乳活跃增殖的初始阶段，随后是胚以胚乳为代价快速生长的第二阶段。由于成熟种子的大小主要是在初始阶段获得的，因此种子大小受母体胚珠、胚乳和胚的生长协调调节。种子大小控制的机制仍然没有得到很好的理解，但种子构成了人类饮食的大部分。SHB 1基因是拟南芥种子发育的正调节因子，通过调节细胞大小和细胞数量来发挥作用。shb 1-D，一个功能获得的等位基因，增加种子大小，而shb 1，一个功能丧失的等位基因，减少种子大小。Shb 1-D的种子大小的增加与胚乳细胞化的时间，合点胚乳的扩大，以及随后的胚胎发育。SHB 1调节MINI 3和IKU 2基因的表达，MINI 3和IKU 2基因分别编码WRKY转录因子和LRR受体激酶。 SHB 1在体内与MINI3和IKU 2启动子结合，并直接与MINI3相互作用。本项目的目标是测试SHB 1是否被WRKY转录因子招募为共激活因子，以控制胚乳发育所需的基因表达。各种细胞，生物化学和分子方法将用于研究SHB 1与MINI3的相互作用以及SHB 1-MINI3相互作用的生物学后果。了解种子大小的调节机制有可能产生潜在的种子产量的增加和蛋白质和油的产量的增加。本项目将提供良好的机会，本科生，研究生和博士后获得重要的研究经验，最重要的是，培养他们的批判性分析和解决科学问题的能力。种子大小是一种产量性状，传统的植物育种在改善方面取得的成功有限。主要种子作物如大豆和油菜的种子发育遵循与拟南芥非常相似的路径。提高大种子大小的潜力是最有希望和探索最少的途径之一，以产生显着增加农业产量。

PI: Min NiProposal number: IOS-0919886Proposal Title: "SHB1 regulates seed development in Arabidopsis"Double fertilization in angiosperms leads to the formation of a diploid embryo and a triploid endosperm. In Arabidopsis, seed development undergoes an initial phase of active endosperm proliferation followed by a second phase in which embryo grows rapidly at the expense of the endosperm. Since mature seed size is largely attained during the initial phase, seed size is coordinately regulated by the growth of the maternal ovule, the endosperm, and the embryo. The mechanisms underlying seed size control are still not well understood, yet seeds form the bulk of the diet of human population. The gene SHB1 is a positive regulator of Arabidopsis seed development that operates through regulation of both cell size and cell number. shb1-D, a gain-of-function allele, increases seed size and shb1, a loss-of-function allele, reduces seed size. The increase in seed size of shb1-D is associated with the timing of endosperm cellularization, enlargement of chalazal endosperm, and subsequent embryo development. SHB1 regulates the expression of the genes MINI3 and IKU2, which encode a WRKY transcription factor and an LRR receptor kinase respectively. SHB1 associates with MINI3 and IKU2 promoters in vivo, and directly interacts with MINI3. The goal of this project is to test if SHB1 is recruited as a co-activator by a WRKY transcription factor to control gene expression required for endosperm development. Various cellular, biochemical, and molecular approaches will be used to investigate the interaction of SHB1 with MINI3 and the biological consequence of SHB1-MINI3 interaction. Understanding the mechanisms of seed size regulation has the potential to generate a potential increase in seed yield and a concomitant increase in the amount of protein and oil produced per seed.This project will provide excellent opportunities for undergraduates, graduate students, and postdoctoral fellows to gain significant research experiences, and most importantly, to develop their ability to critically analyze and solve scientific problems. Seed size is a yield trait that traditional plant breeding has limited success in improving. Seed development in major seed crops such as soybean and canola follows a very similar path to Arabidopsis. Enhancing the potential for large seed size represents one of the most promising and least explored avenues for generating a significant increase in agricultural yield.