Oxylipin Mediated Crosstalk Governs Maize-Fungal Interactions

Pi：Michael V.KolomietsCo-PI：Nancy P.Keller Proposal number：NSF 0544428 Proposal number：NSF 0544428 Proposal标题：氧化脂质介导的串扰控制玉米与真菌的相互作用世界范围内种子生产的一个主要限制因素是大量作物受到产生有毒、致畸和致癌真菌毒素的真菌的污染。越来越多的证据表明，一种叫做加氧脂(由保守的加氧酶产生的含氧脂肪酸)的小分子在种子/真菌/真菌毒素的相互作用中是重要的。最近的数据表明，玉米9-脂氧合酶衍生的氧脂在霉菌毒素产生菌曲霉和镰刀菌产生的孢子和真菌毒素中起着关键作用。这些数据提出了一种假设，即9-脂氧合酶(LOX)衍生物是植物中的敏感因子，作为增加玉米真菌产孢量和真菌毒素产生的信号。这项研究将检验的中心假设是，黄曲霉和玉米诱导、拦截和识别彼此的氧脂，这反过来又指导玉米/真菌/真菌毒素相互作用的结果。这将实现：(1)通过扰乱玉米品系中所有对黄曲霉毒素积累的抗性水平相反的9-LOX基因；(2)通过扰乱黄曲霉中产生氧脂的加氧酶；以及(3)通过利用玉米和真菌突变体阐明曲霉/玉米相互作用中对氧脂的需求。这项研究有望为控制植物-病原菌相互作用结果的跨王国基于脂质的信号传递提供确凿证据。这些结果将对更大的科学界具有重要意义，这些科学界不仅参与了植物-病原体之间的串扰信号研究，而且还参与了动物-人类-病原体相互作用的研究。这一提议的更广泛影响可能导致将真菌毒素抗性纳入商业生产线的生产，这对普通公众、种子行业、玉米种植者和育种者具有重大和直接的意义。此外，这项建议将在植物和真菌遗传学、分子生物学和生物化学等跨学科领域对研究生和博士后研究员进行培训和教育，并在实验室和课堂环境中指导本科生。

PI: Michael V. KolomietsCo-PI: Nancy P. KellerProposal Number: NSF 0544428Proposal Title: Oxylipin Mediated Crosstalk Governs Maize-Fungal InteractionsA major constraint of seed production worldwide is contamination of a large number of crops with fungi that produce toxic, teratogenic and carcinogenic mycotoxins. Accumulating evidence suggests that a subset of small molecules called oxylipins (oxygenated fatty acids produced by conserved oxygenases) are important in the seed/fungal/mycotoxin interaction. Recent data suggests that maize 9-lipoxygenase-derived oxylipins play a pivotal role in spore and mycotoxin production by the mycotoxin producing genera Aspergillus and Fusarium. These data prompted a hypothesis that 9-lipoxygenase (LOX) derivatives are susceptibility factors in plants that act as signals to increase fungal sporulation and mycotoxin production in maize. The central hypothesis that will be tested by this study is that A. flavus and maize induce, intercept and recognize each others oxylipins which in turn directs the outcome of the maize/fungal/mycotoxin interaction. This will be accomplished: (1) by disrupting all 9-LOX genes in corn lines that contrast in the level of resistance to aflatoxin accumulation; (2) by disrupting oxylipin-producing oxygenases in A. flavus; and (3) by elucidating the requirement of oxylipins in the Aspergillus/maize interaction using maize and fungal mutants. This study is expected to generate conclusive evidence of cross kingdom lipid-based signaling communication that governs the outcomes of plant-pathogen interactions. These results will be of great significance to a larger scientific community involved in the studies of cross-talk signaling not only in plant-pathogen but also in animal- and human-pathogen interactions. The broader impacts of this proposal could result in production of mycotoxin resistance incorporated into commercial lines that is of great and immediate significance for the general public, seed industry, maize growers and breeders. Furthermore this proposal will result in training and education of graduate students and postdoctoral fellows in cross-disciplinary fields of plant and fungal genetics, molecular biology and biochemistry and mentoring of undergraduates in laboratory and class settings.