Investigating the Effects of Plant Hormones on Intercellular Trafficking via Plasmodesmata

项目概要/摘要 胞间连丝（PD），植物细胞壁中的质膜内衬孔，允许运输 小分子、大分子、代谢物、信号分子和包括来自 从一个植物细胞到另一个已经发现几种激素通过PD在细胞之间运输。 有趣的是，水杨酸（SA），一种植物防御激素，不通过PD，而是通过 质外体尽管如此，SA是一种重要的激素信号，它对细胞间的相互作用起着负调节作用。 响应病原体感染的渗透性。先前的研究表明SA调节PD 通过调节胼胝质沿着孔沿着积累。PD的第二个作用是诱导 在现有PD处插入额外的孔，导致形成复杂（分支）孔。 由于PD对植物生长、发育和防御非常重要，我们寻求 了解参与调节PD功能和形成的分子机制。这 研究将集中于研究SA如何调节细胞间的细胞机制， 通过调节PD渗透性来运输。这些研究将结合先进的 显微技术和细胞及分子生物学方法来研究SA是如何连接的 烟草（Nicotiana benthamiana）叶表皮组织中PD转运的研究的具体目标 研究将确定SA单独或与另一种防御激素组合的效果， 茉莉酸对PD结构和功能的影响。我们还将研究SA的浓度 和/或JA基于暴露于激素后的不同时间改变PD渗透性（目的 1）确定PD结构和SA处理的组织中相对于未处理的组织的PD数量 对照检查激素对PD形成的影响（目的2）;确定SA对PD形成的影响。 内吞作用和ER-PM接触位点作为将新孔插入现有细胞的过程的一部分 墙，（目标3）。这项研究的结果将促进对激素如何影响人类健康的理解。 影响细胞间运输和PD，它们将引起基础植物科学家的兴趣， 农业科学家。

PROJECT SUMMARY/ABSTRACT Plasmodesmata (PD), plasma membrane-lined pores in the plant cell walls, allow trafficking of small molecules, macromolecules, metabolites, signaling molecules and including hormones from one plant cell to another. Several hormones have been found to traffic between cells via PD. Interestingly, salicylic acid (SA), a plant defense hormone, does not traffic via PD but through the apoplast. Nonetheless, SA is a critical hormonal signal that negatively regulates cell-to-cell permeability in response to pathogen infection. Previous studies have shown SA to regulate PD through regulated callose accumulation along the pores. A second effect of PD is to induce the insertion of additional pores at existing PD leading to the formation of complex (branched) pores. Because PD are very important for plant growth, development, and defense, we seek to understand the molecular mechanisms involved in regulating PD function and formation. This study will focus on investigating the cellular mechanisms of how SA regulates intercellular trafficking by adjusting PD permeability. These studies will apply a combination of advanced microscopic techniques and cell and molecular biology approaches to study how SA is connected to PD transport in epidermal leaf tissues of Nicotiana benthamiana. The specific aims of the research will determine the effects of SA alone or in combination with another defense hormone, jasmonic acid, on PD structure and function. We will also investigate how the concentration of SA and/or JA change PD permeability based on various times after exposure to the hormone (Aim 1); determine PD structure and the number of PD in SA-treated tissues relative to untreated controls to examine hormone effects on PD formation (Aim 2); determine the effect of SA on endocytosis and ER-PM contact sites as part of the process inserting new pores into existing cell walls, (Aim 3). The results from this research will advance understanding of how hormones influence intercellular trafficking and PD, and they will be of interest to basic plant scientists and agricultural scientists.