Examining the Role of the Endomebrane in Transcription Factor Movement

智力智力为了使生物体正常发育和发挥作用，生物体内的细胞必须能够相互交流。在植物中，通讯可以通过称为胞间连丝的特殊细胞间通道进行。植物中几乎所有的细胞都通过胞间连丝相连，胞间连丝允许细胞之间直接交换蛋白质。这意味着，一个细胞产生的蛋白质可以进入邻近细胞，并影响邻居的行为和/或发育命运。细胞信号传递中的一个重要问题是这种类型的蛋白质运动是如何调节的。最近，这位首席研究员发现了一种被她称为SIEL(短根相互作用胚胎致死)的蛋白质，它促进了一种名为短根(SHR)的植物编码的转录因子在细胞之间的移动。SHR的运动是植物根系正常形成和生长所必需的，因此也是植物整体生长所必需的。除了SHR，SIEL还与其他几个对植物生长重要的可移动转录因子相互作用。SIEL很可能促进了植物生长中其他关键蛋白质的移动，因为导致SIEL不产生的突变会导致植物在胚胎发育早期死亡。目前的数据表明，SIEL作为细胞内的穿梭分子，通过与细胞间膜(特别是内小体)和微管细胞骨架的联系来促进依赖于胞间连丝的蛋白质运动。该项目的目标是确定SIEL如何在植物发育过程中蛋白质的细胞间运输中发挥作用。这项研究与植物发育和细胞生物学有明显的相关性。此外，由于植物病毒被认为利用内源植物途径进行细胞间运动，因此与植物抗病和农业有关，在这些地方，病毒感染可以使作物产量大幅下降。更广泛的IMPACTST首席调查员经营着一个实验室，在这个实验室中，高度鼓励各级学生参与研究。她接待过当地初中和高中的学生，每天都有高中生和本科生在她的实验室里积极工作。此外，她还积极与当地教师和宾夕法尼亚大学教育专业的一名学生合作，开发实验室练习，这些练习可以在网上或当地杂货店或园艺商店使用廉价且容易获得的材料进行。这些实验室练习符合宾夕法尼亚州科学教育的标准和基准。

INTELLECTUAL MERITIn order for organisms to develop and function properly, cells within the organism must be able to communicate with each other. In plants, communication can occur through specialized intercellular channels called plasmodesmata. Nearly all cells in the plant are connected through plasmodesmata, which allow for the direct exchange of proteins between cells. This means that proteins made by one cell can travel into the neighboring cell and influence the behavior and/or developmental fate of the neighbor. An important question in cell signaling is how this type of protein movement is regulated. Recently the primary investigator identified a protein that she has called SIEL (for SHORT-ROOT INTERACTING EMBRYONIC LETHAL) that promotes the movement of a plant-encoded transcription factor called SHORT-ROOT (SHR) between cells. Movement of SHR is required for the proper formation and growth of the plant root and therefore overall growth of the plant. In addition to SHR, SIEL also interacts with several other mobile transcription factors that are important for plant growth. It is likely that SIEL promotes the movement of other key proteins in plant growth as mutations that cause SIEL not to be produced result in death of the plant early in embryo development. Current data suggest that SIEL acts as an intracellular shuttle that promotes plasmodesmata-dependent movement of proteins through associations with intercellular membranes (specifically endosomes) and the microtubule cytoskeleton. The goal of this project is to determine how SIEL functions in the cell-to-cell transport of proteins during plant development. This research has obvious relevance to plant development and cell biology. In addition, as plant viruses are thought to exploit endogenous plant pathways for intercellular movement, there is relevance to plant disease resistance and agriculture where viral infections can decimate crop yields. BROADER IMPACTSThe primary investigator runs a laboratory in which research participation by students at all levels is highly encouraged. She has hosted students from the local middle schools and high schools and has both high school and undergraduate students actively working in her laboratory on a daily basis. In addition she has actively engaged with local teachers and a Penn education major to develop laboratory exercises that can be performed with materials inexpensively and readily available online or in local grocery or gardening stores. These laboratory exercises meet Pennsylvania standards and benchmarks for science education.