Genetic and Molecular Analysis of Cellular Interactions in Arabidopsis

本提案中描述的工作的总体目标是了解植物细胞如何相互通信。 为了研究这一点，研究人员分析了男性和女性生殖系统之间必须发生的相互作用，以便成功受精。 这些包括许多不同的相互作用，这些相互作用是控制诸如水从柱头转移到花粉粒、花粉粒获得极性和将生长中的花粉管引导到单个胚珠等不同过程所必需的。 这位研究者对这一问题进行了遗传学研究，确定了导致不育但不是由于生殖系统形态改变的突变。 他已经鉴定了一类主要的雄性不育突变体，它们不能被柱头识别，并且似乎缺乏长链脂质物质的产生。 他还鉴定了许多改变胚珠发育的突变，并利用这些突变确定胚珠内所含的单倍体胚囊对于子房内花粉管的正确引导是必不可少的。 实验提出了扩展这些突变的表征，以及确定新的突变，包括那些活跃在植物生命周期的单倍体阶段。 这一授权期的具体目标是：（1）尽可能多地鉴定专门参与控制生长和发育的基因;（2）通过分析其表型，确定已在遗传学上鉴定的基因在生殖过程中的功能。

The overall goal of the work described in this proposal is to understand how plant cells communicate with one another. To study this, this investigator analyzes the interactions that must take place between the male and female reproductive systems in order for fertilization to take place successfully. These encompass many different interactions which are required to control such diverse processes as the transfer of water from the stigma to the pollen grain, the acquisition of polarity by the pollen grain and the guidance of the growing pollen tube to an individual ovule. This investigator has undertaken a genetic approach to this problem, identifying mutations which result in sterility but are not due to the altered morphology of the reproductive system. He has identified one major class of male sterile mutants which fail to be recognized by the stigma and appear to be deficient in the production of long chain lipid species. He has also identified numerous mutations which alter the development of the ovules and has used these to determine that the haploid embryo sac contained within the ovule is essential for the proper guidance of the pollen tubes within the ovary. Experiments are proposed to extend the characterization of these mutations as well as to identify new mutations, including those which are active in the haploid phase of the plant life cycle. Specific objectives for this granting period are: (1) to identify as many genes as possible which are specifically involved in the control of the growth and development; and (2) to characterize the functions of the genes already identified genetically in the reproductive process by an analysis of their phenotypes.