Kimura Sachie, Waszczak Cezary, Hunter Kerri, Wrzaczek Michael
Division of Plant Biology, Department of Biosciences, Viikki Plant Science Centre, University of Helsinki, FI-00014 Helsinki, Finland.
Division of Plant Biology, Department of Biosciences, Viikki Plant Science Centre, University of Helsinki, FI-00014 Helsinki, Finland
Plant Cell. 2017 Apr;29(4):638-654. doi: 10.1105/tpc.16.00947. Epub 2017 Apr 3.
In plants, receptor-like kinases (RLKs) and extracellular reactive oxygen species (ROS) contribute to the communication between the environment and the interior of the cell. Apoplastic ROS production is a frequent result of RLK signaling in a multitude of cellular processes; thus, by their nature, these two signaling components are inherently linked. However, it is as yet unclear how ROS signaling downstream of receptor activation is executed. In this review, we provide a broad view of the intricate connections between RLKs and ROS signaling and describe the regulatory events that control and coordinate extracellular ROS production. We propose that concurrent initiation of ROS-dependent and -independent signaling linked to RLKs might be a critical element in establishing cellular responses. Furthermore, we discuss the possible ROS sensing mechanisms in the context of the biochemical environment in the apoplast. We suggest that RLK-dependent modulation of apoplastic and intracellular conditions facilitates ROS perception and signaling. Based on data from plant and animal models, we argue that specific RLKs could be components of the ROS sensing machinery or ROS sensors. The importance of the crosstalk between RLK and ROS signaling is discussed in the context of stomatal immunity. Finally, we highlight challenges in the understanding of these signaling processes and provide perspectives for future research.
在植物中，类受体激酶（RLKs）和细胞外活性氧（ROS）有助于环境与细胞内部之间的通讯。质外体ROS的产生是众多细胞过程中RLK信号传导的常见结果；因此，就其本质而言，这两个信号成分存在内在联系。然而，受体激活下游的ROS信号传导是如何执行的，目前尚不清楚。在本综述中，我们全面审视了RLKs与ROS信号传导之间的复杂联系，并描述了控制和协调细胞外ROS产生的调控事件。我们提出，与RLKs相关的ROS依赖性和非依赖性信号传导的同时启动可能是建立细胞反应的关键因素。此外，我们在质外体生化环境的背景下讨论了可能的ROS感知机制。我们认为，RLK对质外体和细胞内条件的依赖性调节促进了ROS的感知和信号传导。基于植物和动物模型的数据，我们认为特定的RLKs可能是ROS感知机制或ROS传感器的组成部分。在气孔免疫的背景下讨论了RLK与ROS信号传导之间相互作用的重要性。最后，我们强调了理解这些信号传导过程所面临的挑战，并为未来的研究提供了展望。
