Role of Arabidopsis SFD1 in Systemic Acquired Resistance

系统获得抗性是植物中的一种诱导型防御机制，其赋予对广谱病原体的增强抗性。 SAR的激活需要一个未知因子通过韧皮部的移位。 拟南芥SFD 1基因编码二羟丙酮磷酸（DHAP）还原酶，是SAR所必需的。 DHAP还原酶催化DHAP和甘油-3-磷酸的相互转化，其为甘油脂质生物合成提供甘油骨架。 脂质代谢在sfd 1突变体中改变，表明脂质在SAR中具有重要作用。 本提案的长期目标是研究SFD 1在SAR中的作用，从而验证上述假设。为了实现这些目标，将寻求遗传，分子和生化方法的组合来表征SFD 1的生化功能。 此外，SFD 1衍生因子在韧皮部中的作用，在SAR的激活过程中，将解决一种新的生物测定结合高灵敏度的质谱方法。 本文的研究将有助于进一步理解SAR中的长距离信号传输。该项目将提供一个极好的机会，通过将目前的脂质代谢知识和植物胁迫反应的遗传、分子和生物化学基础带入课堂，将最先进的研究和教育结合起来。 除了向研究生和博士后研究员提供培训外，该项目还将使本科生参与生物科学研究，并扩大代表性不足群体的参与。 尤其是一个非博士的本科生，每年夏天将招募资助机构参与该项目。 该项目的成果将对整个社会产生潜在的惠益。 拟议研究确定的脂质可以为增强植物抗病性提供新的靶点，从而限制使用有毒化学品来保护植物，从而改善我们的环境和健康质量。

Systemic acquired resistance is an inducible defense mechanism in plants that confers enhanced resistance against a broad-spectrum of pathogens. The activation of SAR requires the translocation of an unknown factor through the phloem. The Arabidopsis thaliana SFD1 gene, which encodes a dihydroxyacetone phosphate (DHAP) reductase, is required for SAR. DHAP reductases catalyze the interconversion of DHAP and glycerol-3-phosphate, which provides the glycerol backbone for glycerolipid biosynthesis. Lipid metabolism is altered in the sfd1 mutant, suggesting that a lipid(s) has an important role in SAR. The long-term objectives of this proposal are to study the role of SFD1 in SAR, thereby testing the above hypothesis. To achieve these objectives, a combination of genetic, molecular and biochemical approaches will be pursued to characterize the biochemical function of SFD1. In addition, the role of a SFD1-derived factor in the phloem during the activation of SAR will be addressed with a novel bioassay in combination with highly sensitive mass-spectrometric approaches. The proposed research will contribute greatly to the understanding of long-distance signaling in SAR. The project will provide an excellent opportunity to integrate state-of-the-art research and education by bringing current knowledge of lipid metabolism and the genetic, molecular and biochemical basis of plant stress responses into the classroom. In addition to providing training to graduate students and post doctoral fellows, this project will engage undergraduates in research in the biological sciences and broaden the participation of underrepresented groups. In particular, an undergraduate student from a non-Ph.D.-granting institution will be recruited to work on the project each summer. Results from this project will have potential benefits to society at large. The lipid(s) identified by the proposed study could provide new targets for enhancing disease resistance in plants, thus limiting the utilization of toxic chemicals to protect plants, thereby improving the quality of our environment and health.