Regulation of defense signaling in tomato

描述（由申请人提供）：多不饱和脂肪酸（PUFA）的氧化代谢产生一组含氧化合物，称为氧脂素，可调节多细胞生物体的基本生理过程。我们的长期研究目标是了解氧脂素合成和代谢的一般原理，并剖析这些生物活性物质调节防御相关过程的分子机制。在本申请中，我们将建立在我们以前的成功，建立番茄（番茄）作为一个模型系统的分子遗传分析系统诱导的抗草食性节肢动物。该研究旨在验证以下假设：脂肪酸衍生的植物激素茉莉酸（JA）是宿主防御反应的细胞间信号，JA的生物合成受肽信号系统素的调节。该项目的具体目标是：（一）利用图位法克隆和鉴定在系统素感知中发挥作用的Spr 1基因;（二）完成JA的环戊烯酮前体12-氧代植物二烯酸代谢或转运所需的JL 1基因的图位克隆;（iii）使用遗传嵌合体分析JA生物合成和JA感知在细胞间创伤信号传导中的作用;和（iv）结合联合收割机生物化学和功能测定以分析韧皮部渗出物中JA、系统素和诱导防御基因表达的其它信号的存在。 systemin/JA信号通路提供了一个独特的机会，研究肽和oxlipin信号协调全身免疫的机制。植物中PUFA氧化代谢的生物化学途径与花生四烯酸衍生化合物的生产中所涉及的生物化学途径非常相似，花生四烯酸衍生化合物在人类健康和疾病的许多方面发挥着重要作用。因此，拟议的研究有望阐明不同生物系统中氧脂素代谢的一般原理。从这些研究中获得的结果也将提供深入了解脂肪酸衍生的信号调节宿主防御反应的具体机制，更普遍的是，PUFA在健康和患病生物体中的作用。

DESCRIPTION (provided by applicant): Oxidative metabolism of polyunsaturated fatty acids (PUFAs) gives rise to a group of oxygenated compounds, called oxylipins, which regulate essential physiological processes in multicellular organisms. Our long-term research objective is to understand the general principles governing the synthesis and metabolism of oxylipins, and to dissect the molecular mechanisms by which these bioactive substances regulate defense-related processes. In the present application, we will build on our previous success in establishing Lycopersicon esculentum (tomato) as a model system for molecular genetic analysis of systemic induced resistance to herbivorous arthropods. The proposed research seeks to test the hypothesis that the fatty acid-derived plant hormone jasmonic acid (JA) is an intercellular signal for host defense responses, and that the biosynthesis of JA is regulated by the peptide signal systemin. The specific aims of the project are: (i) to use a map-based approach to clone and characterize the Sprl gene that plays a role in systemin perception; (ii) to complete map-based cloning of the JL1 gene that is required for the metabolism or transport of 12-oxo-phytodienoic acid, a cyclopentenone precursor of JA; (iii) to use genetic chimeras to analyze the role of JA biosynthesis and JA perception in intercellular wound signaling; and (iv) to combine biochemical and functional assays to analyze phloem exudate for the presence of JA, systemin, and other signals that induce defense gene expression. The systemin/JA signaling pathway provides a unique opportunity to study the mechanism by which peptide and oxylipin signals coordinate systemic immunity. The biochemical pathways for oxidative metabolism of PUFAs in plants are remarkably similar to those involved in the production of arachidonic acid-derived compounds that play an essential role in numerous aspects of human health and disease. Thus, the proposed research is expected to illuminate general principles of oxylipin metabolism in diverse biological systems. Results obtained from these studies will also provide insight into specific mechanisms by which fatty acid-derived signals regulate host defense responses and, more generally, the role of PUFAs in healthy and diseased organisms.