Organismal and Evolutionary Biology, Viikki Plant Science Centre (ViPS), University of Helsinki, Finland.
Photochem Photobiol Sci. 2019 May 15;18(5):970-988. doi: 10.1039/c8pp00526e.
Plants perceive ultraviolet-B (UV-B) radiation through the UV-B photoreceptor UV RESISTANCE LOCUS 8 (UVR8), and initiate regulatory responses via associated signalling networks, gene expression and metabolic pathways. Various regulatory adaptations to UV-B radiation enable plants to harvest information about fluctuations in UV-B irradiance and spectral composition in natural environments, and to defend themselves against UV-B exposure. Given that UVR8 is present across plant organs and tissues, knowledge of the systemic signalling involved in its activation and function throughout the plant is important for understanding the context of specific responses. Fine-scale understanding of both UV-B irradiance and perception within tissues and cells requires improved application of knowledge about UV-attenuation in leaves and canopies, warranting greater consideration when designing experiments. In this context, reciprocal crosstalk among photoreceptor-induced pathways also needs to be considered, as this appears to produce particularly complex patterns of physiological and morphological response. Through crosstalk, plant responses to UV-B radiation go beyond simply UV-protection or amelioration of damage, but may give cross-protection over a suite of environmental stressors. Overall, there is emerging knowledge showing how information captured by UVR8 is used to regulate molecular and physiological processes, although understanding of upscaling to higher levels of organisation, i.e. organisms, canopies and communities remains poor. Achieving this will require further studies using model plant species beyond Arabidopsis, and that represent a broad range of functional types. More attention should also be given to plants in natural environments in all their complexity, as such studies are needed to acquire an improved understanding of the impact of climate change in the context of plant-UV responses. Furthermore, broadening the scope of experiments into the regulation of plant-UV responses will facilitate the application of UV radiation in commercial plant production. By considering the progress made in plant-UV research, this perspective highlights prescient topics in plant-UV photobiology where future research efforts can profitably be focussed. This perspective also emphasises burgeoning interdisciplinary links that will assist in understanding of UV-B effects across organisational scales and gaps in knowledge that need to be filled so as to achieve an integrated vision of plant responses to UV-radiation.
植物通过 UV-B 光受体 UV 抗性位点 8（UVR8）感知紫外线-B（UV-B）辐射，并通过相关信号网络、基因表达和代谢途径启动调节反应。各种对 UV-B 辐射的调节适应使植物能够获取有关自然环境中 UV-B 辐照度和光谱组成波动的信息，并保护自己免受 UV-B 暴露。鉴于 UVR8 存在于植物器官和组织中，了解其在整个植物中的激活和功能的系统信号对于理解特定反应的背景非常重要。在组织和细胞内对 UV-B 辐射和感知的精细理解需要改进对叶片和冠层中 UV 衰减的知识的应用，在设计实验时需要更多地考虑这一点。在这种情况下，还需要考虑光受体诱导途径之间的相互串扰，因为这似乎会产生特别复杂的生理和形态反应模式。通过串扰，植物对 UV-B 辐射的反应不仅仅是简单的 UV 保护或减轻损伤，而是可以提供一系列环境胁迫因素的交叉保护。总的来说，越来越多的知识表明 UVR8 捕获的信息如何用于调节分子和生理过程，尽管对组织水平更高的信息的理解，即生物体、冠层和群落，仍然很差。要实现这一点，需要使用除拟南芥以外的模式植物物种进行进一步研究，并代表广泛的功能类型。还应该更加关注自然环境中的植物，因为需要进行这些研究，才能更好地了解气候变化对植物-UV 反应的影响。此外，将实验范围扩大到植物-UV 反应的调节将有助于将紫外线辐射应用于商业植物生产。通过考虑植物-UV 研究取得的进展，本观点突出了植物-UV 光生物学中具有前瞻性的主题，未来的研究工作可以集中在这些主题上。本观点还强调了新兴的跨学科联系，这将有助于理解跨组织尺度的 UV-B 效应以及需要填补的知识空白，以便实现对植物对 UV 辐射反应的综合认识。
