Leucine Aminopeptidase: A Regulator of the Late Branch of Wound Signaling

本研究的重点是了解番茄亮氨酰氨肽酶A（LapA）。在番茄受伤和被昆虫取食后，番茄的防御系统会受到抑制。当转基因LapA-SI植物中的昆虫生长抑制蛋白减少时，拮抗昆虫生长的蛋白质和化学物质以较低的水平产生。LapA-SI植物遭受更多的损害，并且烟草角虫相对于来自野生型植物的昆虫更大。此外，在产生过量LAP-A蛋白（LapA-OX）的植物上，毛虫消耗较少的叶子，幼虫质量减少。LapA-OX植物提供了一种重要的新抗虫机制，因为植物株高和生育力没有受到损害。了解LAP-A如何控制番茄防御将是我们对植物基因调控的一般知识的重要补充。目标1是确定LapA-SI和LapA-OX植物对使用不同进食模式的昆虫的易感性或抗性。如果LapA-OX植物对许多昆虫物种提供抗性，将发现保护植物免受昆虫害虫的重要和新的机制。 目标2是使用遗传、生化和植物转化技术来确定LAP-A的肽酶活性是否对其控制昆虫防御的作用至关重要。这一点很重要，因为来自其他生物体的LAP具有多种功能。最后，目标3是确定由LAP-A调节的细胞过程。提出了一个新的模型，链接的许多信号，影响番茄和LAP-A的伤害。该模型将使用分子、生物化学和转基因植物策略进行严格测试。通过支持或反驳这一模型，这些实验将有助于定义植物对抗昆虫的复杂且基本上未被探索的防御网络。 这些研究将产生新的策略，将对环境安全的抗虫性工程化到作物和园艺植物中，使农业和整个社会受益。拟议的实验范围从整个生物体的研究，分子反应，并跨越植物生物学和昆虫学领域。该研究计划将为研究生和本科生以及博士后研究员提供独特的跨学科培训环境。

This proposal focuses on understanding the tomato leucyl aminopeptidase A (LapA). LAP controls tomato defenses after wounding and insect feeding. When LAP protein is reduced in transgenic LapA-SI plants, the proteins and chemicals that antagonize insect growth are produced at lower levels. LapA-SI plants incur more damage and tobacco hornworms are larger relative to insects from wild-type plants. In addition, on plants that make excessive amounts of LAP-A protein (LapA-OX), caterpillars consume less foliage and larval masses are reduced. The LapA-OX plants provide an important and new mechanism of insect resistance, since plant stature and fertility are not impaired. Understanding how LAP-A controls tomato defenses will be an important addition to our general knowledge of gene regulation in plants. Goal 1 is to determine the susceptibility or resistance of LapA-SI and LapA-OX plants to insects that use different modes of feeding. If LapA-OX plants provide resistance to many insect species, an important and new mechanism to protect plants from insect pests will have been discovered. Goal 2 is to use genetic, biochemical and plant transformation technologies to determine if the peptidase activity of LAP-A is essential for its role in controlling defenses against insects. This is important since LAPs from other organisms have multiple functions. Finally, Goal 3 is to determine the cellular process that is regulated by LAP-A. A new model that links the many signals that influence wounding in tomato and LAP-A is proposed. This model will be rigorously tested using molecular, biochemical and transgenic plant strategies. By supporting or refuting this model, these experiments will aide in defining the complex and largely unexplored defense network that plants employ against insects. These studies should result in new strategies for engineering an environmentally safe resistance to insects into crops and horticultural plants, benefiting agriculture and society at large. The proposed experiments range from whole organism studies to molecular responses and spans the fields of plant biology and entomology. This research program will provide a unique, interdisciplinary training environment for a graduate and undergraduate students and a postdoctoral fellow.