ASSESSING NITRIC OXIDE IN PLANT DEFENSE USING NO SPIN TRAPPING

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 在真核生物和原核生物中，NO在广泛的生理过程中都扮演着信号分子的角色。在植物中，NO参与生长、发育、开花以及对生物和非生物胁迫的响应。已有研究表明，一氧化氮在植物抗病中起着重要作用。然而，与我们对动物没有功能的欣赏不同，植物对刺激的反应的起源和量化仍然不清楚。对NO生物学的全面了解有赖于发展可靠的NO检测方法，EPR是这方面的可靠工具。用自旋陷阱络合物稳定NO自由基，并用ESR检测它，具有选择性和灵敏的优点。用NO自旋陷阱Fe(DETC)2对ACERT进行的初步ESR研究表明，模式植物拟南芥通过更快速和更强劲地产生NO来响应由紫丁香假单胞菌渗透引起的胁迫。Dan Klessig小组感兴趣的是使用亲脂性Fe(DETC)2络合物或亲水性Fe(MGD)2自旋陷阱来评估植物-微生物相互作用中NO的形成：1)植物细胞悬浮液(烟草细胞)与隐孢菌素产生NO，隐孢子菌分泌的一种10 kDa蛋白质诱导宿主防御反应；2)在受细菌病原体(丁香假单胞菌)或与细菌鞭毛蛋白保守域相对应的多肽激发子感染的拟南芥植物中。我们目前使用15N取代来开发ESR测量区分14NO和15NO的能力，我们相信基于ESR的方法将有助于阐明植物中这个自由基的来源(S)。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. NO acts as a signaling molecule in a wide range of physiological processes in both eukaryotes and prokaryotes. In plants, NO participates in growth, development, flowering, and response to biotic and abiotic stresses. It has been shown that nitric oxide plays an important role in plant disease resistance. However, unlike our appreciation of NO functioning in animals, the origin and the quantification of plant NO responses to stimuli remain unclear. A comprehensive understanding of NO biology is dependent on the development of reliable NO detection methods, and EPR represents a reliable tool in this respect. Stabilization of NO radical with spin trap complexes and its detection by ESR offer the advantage of being both selective and sensitive. Initial ESR study in ACERT using NO spin trap Fe(DETC)2 showed that the model plant Arabidopsis thaliana responds to the stress caused by infiltration with Pseudomonas syringae by more rapid and robust production of NO. The Dan Klessig group is interested in using lipophilic Fe(DETC)2 complex or hydrophilic Fe(MGD)2 spin traps to evaluate NO formation in the context of plant-microbe interactions in 1) plant cell suspensions (tobacco cells) elicited for NO production with cryptogein, a 10 kDa protein secreted by the oomycete Phytophtora cryptogea that induces host defense responses, and 2) in Arabidopsis plants infected with either a bacterial pathogen (Pseudomonas syringae) or a peptide elicitor corresponding to the conserved domain of bacterial flagellin. We currently use 15N substitution to exploit the ability of the ESR measurement to distinguish between 14NO and 15NO, and we are confident that an ESR-based approach will help to elucidate the origin(s) of this radical in planta.