Secretion Signals and Type III Chaperones in the Pseudomonas Syringae Type III Secretion System

革兰氏阴性植物和动物病原体的III型蛋白分泌系统（TTSSs）将细菌蛋白（称为效应器）注入真核细胞，从而调节宿主信号转导途径。效应蛋白通过其n端携带的分泌信号和/或通过称为III型伴侣蛋白（TTCs）的特殊辅助蛋白靶向TTSS。增加我们对这些过程的了解可能最终有助于药物和/或农业农药或除草剂的设计。因此，所提出的活动的智力价值是相当显著的，因为增加我们对这一主题的理解可能会导致更好地控制由依赖TTSS的病原体引起的动植物疾病。本课题旨在探讨植物病原菌丁香假单胞菌（Pseudomonas syringae）中TTCs的分泌信号及其在TTSS中的作用。几个实验的目的是确定III型分泌信号的生物学功能。这些实验将利用几种不同的ttss底物，并将重点关注n端分泌信号和/或TTCs（及其结合位点）在效应器的分泌和易位（注射到宿主细胞中）中的作用。本课题的实验对学生进行了全面的训练。PI与内布拉斯加州的一个项目开展了合作，该项目旨在让代表性不足的少数民族学生参与进来，并与当地文理学院的教授合作，帮助那些可能没有足够机会进行研究的学生。

Type III protein secretion systems (TTSSs) of Gram-negative plant and animal pathogens inject bacterial proteins, called effectors, into eukaryotic cells resulting in the modulation of host signal transduction pathways. Effector proteins are targeted to the TTSS by secretion signals carried in their N-termini and/or with the aid of specialized accessory proteins called type III chaperones (TTCs). Increasing our understanding of these processes may ultimately help in the design of pharmaceuticals and/or agricultural pesticides or herbicides. Thus, the intellectual merit of the proposed activity is quite significant because increasing our understanding of this topic may lead to better control of plant and animal diseases caused by pathogens dependent on TTSS. Project experiments were designed to explore the secretion signals used by effectors and the involvement of TTCs in the TTSS of the bacterial plant pathogen Pseudomonas syringae. The goal of several experiments is to determine the biological function of type III secretion signals. These experiments will utilize several different substrates of TTSSs, and will be focused on the role that N-terminal secretion signals and/or TTCs (and their binding sites) play in the secretion and translocation (injection into host cells) of effectors. The experiments in this project offer comprehensive training for students. The PI has initiated collaborations with a Nebraska program that targets the involvement of underrepresented minority students as well as collaborations with professors at local liberal arts colleges to reach students that may not have ample opportunities for a research experience.