Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing 100083, China.
College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
Development. 2020 Jul 13;147(13):dev189902. doi: 10.1242/dev.189902.
The interaction between the receptor-like kinase (RLK) FERONIA (FER) and the secreted peptide RAPID ALKALINIZATION FACTOR1 (RALF1) is vital for development and stress responses in Ligand-induced membrane dynamics affect the function of several RLKs, but the effects of the RALF1-FER interaction on the dynamics of FER and the ensuing effects on its functionality are poorly understood. Here, we show that RALF1 modulated the dynamics and partitioning of FER-GFP at the plasma membrane (PM). Moreover, FER was internalized by both clathrin-mediated endocytosis (CME) and clathrin-independent endocytosis (CIE) under steady-state conditions. After RALF1 treatment, FER-GFP internalization was primarily enhanced via the CME pathway, raising FER-GFP levels in the vacuole. RALF1 treatment also modulated trafficking of other PM proteins, such as PIN2-GFP and BRI1-GFP, increasing their vacuolar levels by enhancing their internalization. Importantly, blocking CME attenuated RALF1-mediated root growth inhibition independently of RALF1-induced early signaling, suggesting that the RALF1 can also exert its effects via the CME pathway. These findings reveal that the RALF1-FER interaction modulates plant growth and development, and this might also involve endocytosis of PM proteins.
受体样激酶（RLK）FERONIA（FER）与分泌肽 RAPID ALKALINIZATION FACTOR1（RALF1）之间的相互作用对于发育和应激反应至关重要。配体诱导的膜动力学影响几种 RLK 的功能，但 RALF1-FER 相互作用对 FER 动力学的影响及其对其功能的后续影响知之甚少。在这里，我们表明 RALF1 调节了 FER-GFP 在质膜（PM）上的动力学和分区。此外，在稳态条件下，FER 通过网格蛋白介导的内吞作用（CME）和网格蛋白非依赖性内吞作用（CIE）被内化。RALF1 处理后，通过 CME 途径主要增强了 FER-GFP 的内化，从而增加了液泡中的 FER-GFP 水平。RALF1 处理还调节其他 PM 蛋白的运输，例如 PIN2-GFP 和 BRI1-GFP，通过增强内化作用增加它们在液泡中的水平。重要的是，阻断 CME 可独立于 RALF1 诱导的早期信号转导减弱 RALF1 介导的根生长抑制，表明 RALF1 也可以通过 CME 途径发挥作用。这些发现表明，RALF1-FER 相互作用调节植物的生长和发育，这也可能涉及 PM 蛋白的内吞作用。
