Department of Plant and Microbial Biology, Program in Genetics, North Carolina State University, Raleigh, NC 27695-7614, USA.
Department of Plant and Microbial Biology, Program in Genetics, North Carolina State University, Raleigh, NC 27695-7614, USA.
Dev Cell. 2018 Nov 5;47(3):306-318.e5. doi: 10.1016/j.devcel.2018.09.022. Epub 2018 Oct 25.
Auxin is a major phytohormone that controls numerous aspects of plant development and coordinates plant responses to the environment. Morphogenic gradients of auxin govern cell fate decisions and underlie plant phenotypic plasticity. Polar auxin transport plays a central role in auxin maxima generation. The discovery of the exquisite spatiotemporal expression patterns of auxin biosynthesis genes of the WEI8/TAR and YUC families suggested that local auxin production may contribute to the formation of auxin maxima. Herein, we systematically addressed the role of local auxin biosynthesis in plant development and responses to the stress phytohormone ethylene by manipulating spatiotemporal patterns of WEI8. Our study revealed that local auxin biosynthesis and transport act synergistically and are individually dispensable for root meristem maintenance. In contrast, flower fertility and root responses to ethylene require local auxin production that cannot be fully compensated for by transport in the generation of morphogenic auxin maxima.
生长素是一种主要的植物激素，它控制着植物发育的许多方面，并协调植物对环境的反应。生长素的形态发生梯度控制着细胞命运的决定，并构成了植物表型可塑性的基础。极性生长素运输在生长素最大值的产生中起着核心作用。WEI8/TAR 和 YUC 家族生长素生物合成基因的精确时空表达模式的发现表明，局部生长素的产生可能有助于生长素最大值的形成。在此，我们通过操纵 WEI8 的时空模式，系统地研究了局部生长素生物合成在植物发育和对胁迫植物激素乙烯的反应中的作用。我们的研究表明，局部生长素的生物合成和运输协同作用，并且单独维持根分生组织是可有可无的。相比之下，花的育性和根对乙烯的反应需要局部生长素的产生，而这种产生在形态发生生长素最大值的产生中不能完全通过运输来补偿。
