Characterization of PiCDPK1 Mediated Signaling Pathways Regulating Pollen Tube Tip Growth

PiCDPK1 介导的调节花粉管尖端生长的信号通路的表征

• 批准号: 0543922
• 负责人: Andrew McCubbin
• 金额: --
• 依托单位: Washington State University
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-01 至 2010-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0543922&HistoricalAwards=false
• 关键词: Characterization; PiCDPK1; Mediated; Signaling; Pathways

Production of seeds or fruits is the goal of most agricultural and horticultural practices. In most cases seed and fruit development requires fertilization of ovules by sperm delivered by pollen. In most flowering plants ovules are enclosed within maternal tissues. To traverse this barrier, pollen produce tubes that penetrate the female tissues by a process known as tip-growth. How this process is regulated is not well understood but is key to plant sexual reproduction and is a potential target for the genetic manipulation of fertilization and seed set.Calcium ions play an important regulatory role in tip-growth and a calcium-regulated enzyme (PiCDPK1), which controls pollen tube growth polarity, has been identified. This enzyme is a protein kinase which regulates downstream signaling components by adding phosphate groups to their protein backbones. The objectives of this project are to characterize two such downstream components using molecular genetic and biochemical approaches. Preliminary results suggest that the phosphorylated forms of these components can mediate the inhibition or enhancement of pollen tube growth. This possibility will be investigated in detail using transgenic approaches.This study will significantly enhance knowledge of signaling events in pollen tube growth and is expected to provide molecular tools with which this process can be manipulated. Furthermore, the results may have broader implications for plant cell signaling as calcium is involved in many aspects of plant growth and development.The proposed research will provide training for a post-doctoral, a graduate and several undergraduate students in a variety of cell and molecular biology techniques. Through summer internships, two high school students per year will gain valuable experience in state of the art molecular biology techniques.

种子或水果的生产是大多数农业和园艺实践的目标。在大多数情况下，种子和果实的发育需要通过花粉传递的精子使胚珠受精。在大多数开花植物中，胚珠被包围在母体组织中。为了穿过这一屏障，花粉通过一种称为尖端生长的过程产生穿透雌性组织的管子。这一过程是如何被调控的还不是很清楚，但它是植物有性繁殖的关键，也是受精和结实的遗传操作的潜在靶标。钙离子在顶端生长中起着重要的调节作用，并且已经鉴定出一种控制花粉管生长极性的钙调节酶(PiCDPK1)。这种酶是一种蛋白激酶，通过在蛋白质骨架上添加磷酸基团来调节下游信号成分。该项目的目标是利用分子遗传学和生物化学方法来表征两个这样的下游成分。初步结果表明，这些组分的磷酸化形式可以介导抑制或促进花粉管的生长。这种可能性将使用转基因方法进行详细的研究。这项研究将显著增强对花粉管生长中信号事件的了解，并有望提供可以操纵这一过程的分子工具。此外，由于钙参与植物生长和发育的许多方面，该结果可能对植物细胞信号转导具有更广泛的影响。拟议的研究将为一名博士后、一名研究生和几名本科生提供各种细胞和分子生物学技术的培训。通过暑期实习，每年有两名高中生将获得最先进的分子生物学技术方面的宝贵经验。