MOE Key Laboratory for Cellular Dynamics, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.
Institute of Science and Technology Austria (ISTA), Am Campus 1, Klosterneuburg, Austria.
Commun Biol. 2024 Sep 4;7(1):1085. doi: 10.1038/s42003-024-06747-9.
The developmental plasticity of the root system plays an essential role in the adaptation of plants to the environment. Among many other signals, auxin and its directional, intercellular transport are critical in regulating root growth and development. In particular, the PIN-FORMED2 (PIN2) auxin exporter acts as a key regulator of root gravitropic growth. Multiple regulators have been reported to be involved in PIN2-mediated root growth; however, our information remains incomplete. Here, we identified ROWY Bro1-domain proteins as important regulators of PIN2 sorting control. Genetic analysis revealed that Arabidopsis rowy1 single mutants and higher-order rowy1 rowy2 rowy3 triple mutants presented a wavy root growth phenotype. Cell biological experiments revealed that ROWY1 and PIN2 colocalized to the apical side of the plasma membrane in the root epidermis and that ROWYs are required for correct PM targeting of PIN2. In addition, ROWYs also affected PIN3 protein abundance in the stele, suggesting the potential involvement of additional PIN transporters as well as other proteins. A global transcriptome analysis revealed that ROWY genes are involved in the Fe availability perception pathway. This work establishes ROWYs as important novel regulators of root gravitropic growth by connecting micronutrient availability to the proper subcellular targeting of PIN auxin transporters.
根系的发育可塑性在植物适应环境中起着至关重要的作用。在许多其他信号中，生长素及其定向的细胞间运输在调节根的生长和发育中起着关键作用。特别是，PIN-FORMED2（PIN2）生长素外排体作为根向重力生长的关键调节剂。已经报道了多种调节剂参与 PIN2 介导的根生长；然而，我们的信息仍然不完整。在这里，我们将 ROWY Bro1 结构域蛋白鉴定为 PIN2 分拣控制的重要调节剂。遗传分析表明，拟南芥 rowy1 单突变体和更高阶的 rowy1 rowy2 rowy3 三突变体表现出波浪形的根生长表型。细胞生物学实验表明，ROWY1 和 PIN2 共定位于根表皮的质膜顶端侧，并且 ROWYs 是 PIN2 正确质膜靶向所必需的。此外，ROWYs 还影响茎中的 PIN3 蛋白丰度，表明可能涉及其他 PIN 转运体以及其他蛋白质。全转录组分析表明，ROWY 基因参与铁可用性感知途径。这项工作通过将微量元素可用性与 PIN 生长素转运体的适当亚细胞靶向联系起来，将 ROWYs 确立为根向重力生长的重要新调节剂。
