Laboratory of Growth Regulators, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science of Palacký University & Institute of Experimental Botany of the Czech Academy of Sciences, Šlechtitelů 27, CZ-783 71, Olomouc, Czech Republic; Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71, Olomouc, Czech Republic.
Department of Chemical Biology and Genetics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71, Olomouc, Czech Republic.
N Biotechnol. 2019 Jan 25;48:44-52. doi: 10.1016/j.nbt.2018.06.003. Epub 2018 Jun 25.
The plant hormone auxin is a key player in the regulation of plant growth and development. Despite numerous studies devoted to understanding its role in a wide spectrum of physiological processes, full appreciation of its function is linked to a comprehensive determination of its spatio-temporal distribution, which plays a crucial role in its mode of action. Conjugation of fluorescent tracers to plant hormones enables sensitive and specific visualization of their subcellular and tissue-specific localization and transport in planta, which represents a powerful tool for plant physiology. However, to date, only a few fluorescently labeled auxins have been developed. We report the synthesis of four novel fluorescently labeled derivatives of indole-3-acetic acid (IAA) in the form of a conjugate with a nitrobenzoxadiazole (NBD) fluorophore together with validation of their biological activity. These compounds, unlike other previously reported auxins fluorescently labeled at N1 position (nitrogen of the indole ring), do not possess auxin activity but rather show dose-dependent inhibition of auxin-induced effects, such as primary root growth inhibition, root hair growth and the auxin reporter DR5::GUS expression. Moreover, the study demonstrates the importance of the character of the linker and optimal choice of the labeling site in the preparation of fluorescently labeled auxins as important variables influencing their biological activity and fluorescent properties.
植物激素生长素是调节植物生长和发育的关键因子。尽管有大量研究致力于了解其在广泛生理过程中的作用，但要全面认识其功能，就必须全面确定其时空分布，这在其作用模式中起着至关重要的作用。将荧光示踪剂与植物激素偶联，能够灵敏而特异地观察到它们在亚细胞和组织特异性定位和在植物体内的运输，这是植物生理学的有力工具。然而，迄今为止，只有少数荧光标记的生长素被开发出来。我们报告了以硝基苯并二唑（NBD）荧光团为缀合物的四种新型吲哚-3-乙酸（IAA）荧光标记衍生物的合成，并验证了它们的生物活性。与其他以前报道的在 N1 位（吲哚环的氮）荧光标记的生长素不同，这些化合物不具有生长素活性，而是表现出对生长素诱导效应的剂量依赖性抑制，如主根生长抑制、根毛生长和生长素报告基因 DR5::GUS 的表达。此外，该研究还证明了在制备荧光标记生长素时，连接基团的性质和标记位置的最佳选择作为影响其生物活性和荧光性质的重要变量的重要性。
