Asymmetric division of the zygote and suspensor formation in Arabidopsis

在高等植物中，受精卵的分裂是不对称的，并建立两种根本不同的细胞类型：受精卵的较小的子体承担胚胎细胞的命运，而较大的子体形成主要的胚外胚柄。这项研究的长期目标是了解负责这一基本细胞命运决定的信号事件。P.I.之前的工作导致了有丝分裂原活化蛋白激酶基因YDA的发现，该基因作为分子开关的一部分发挥作用以调节胚外细胞的命运。本项目将通过以下方式进一步表征模式植物拟南芥中的YDA信号转导途径：（1）用分子生物学和组织学的标准方法表征受体样蛋白激酶基因SSP，该基因被预测将YDA功能与细胞表面受体的活化联系起来;（2）用遗传学和生物化学方法鉴定信号链的未知组分。这项研究将阐明植物胚胎发育的一个基本方面，对培养中有效生产植物胚胎和幼苗具有潜在的重要意义。该项目将为博士后研究人员以及本科生和高中生提供尖端分子生物学和遗传学的培训机会。

In higher plants, the division of the zygote is asymmetric and establishes two fundamentally different cell types: the smaller daughter of the zygote assumes an embryonic cell-fate, while the larger daughter forms the mainly extra-embryonic suspensor. The long-term goal of this research is to understand the signaling events responsible for this fundamental cell-fate decision. Previous work by the P.I. has led to the discovery of a mitogen-activated protein kinase kinase kinase gene, YDA, that functions as part of a molecular switch to regulate extra-embryonic cell fates. This project will further characterize the YDA signal transduction pathway in the model plant Arabidopsis by: (1) characterizing the receptor-like protein kinase gene SSP, which is predicted to link YDA function to the activation of a cell surface receptor, with standard methods of molecular biology and histology; (2) identifying as yet unknown components of the signaling chain with genetic and biochemical approaches. This research will elucidate a fundamental aspect of plant embryonic development with potentially important results for the efficient production of plant embryos and seedlings in culture. The project will provide training opportunities for a postdoctoral researcher as well as undergraduate and high school students in cutting edge molecular biology and genetics.