Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA; email:
Department of Anesthesiology, Weill Cornell Medicine, New York, NY, USA; email:
Annu Rev Plant Biol. 2023 May 22;74:415-452. doi: 10.1146/annurev-arplant-070522-033255. Epub 2023 Feb 28.
Plant glutamate receptor-like (GLR) genes encode ion channels with demonstrated roles in electrical and calcium (Ca) signaling. The expansion of the GLR family along the lineage of land plants, culminating in the appearance of a multiclade system among flowering plants, has been a topic of interest since their discovery nearly 25 years ago. GLRs are involved in many physiological processes, from wound signaling to transcriptional regulation to sexual reproduction. Emerging evidence supports the notion that their fundamental functions are conserved among different groups of plants as well. In this review, we update the physiological and genetic evidence for GLRs, establishing their role in signaling and cell-cell communication. Special emphasis is given to the recent discussion of GLRs' atomic structures. Along with functional assays, a structural view of GLRs' molecular organization presents a window for novel hypotheses regarding the molecular mechanisms underpinning signaling associated with the ionic fluxes that GLRs regulate. Newly uncovered transcriptional regulations associated with GLRs-which propose the involvement of genes from all clades of in ways not previously observed-are discussed in the context of the broader impacts of GLR activity. We posit that the functions of GLRs in plant biology are probably much broader than anticipated, but describing their widespread involvement will only be possible with () a comprehensive understanding of the channel's properties at the molecular and structural levels, including protein-protein interactions, and () the design of new genetic approaches to explore stress and pathogen responses where precise transcriptional control may result in more precise testable hypotheses to overcome their apparent functional redundancies.
植物谷氨酸受体样（GLR）基因编码离子通道，其在电信号和钙（Ca）信号中具有明确的作用。GLR 家族沿着陆地植物的进化线扩张，最终在开花植物中出现了多分支系统，自近 25 年前发现以来，一直是人们关注的话题。GLR 参与许多生理过程，从创伤信号到转录调控到有性繁殖。新出现的证据支持这样一种观点，即它们的基本功能在不同植物群体中也是保守的。在这篇综述中，我们更新了 GLR 的生理和遗传证据，确立了它们在信号转导和细胞间通讯中的作用。特别强调了最近关于 GLR 原子结构的讨论。除了功能测定外，GLR 分子组织的结构观点为与 GLR 调节的离子通量相关的信号分子机制提供了新的假设窗口。与以前观察到的方式不同，与 GLR 相关的新发现的转录调控——这些调控涉及所有分支的基因——在 GLR 活性的更广泛影响的背景下进行了讨论。我们假设，GLR 在植物生物学中的功能可能比预期的广泛得多，但要描述它们的广泛参与，只有在（）全面了解通道在分子和结构水平上的特性，包括蛋白质-蛋白质相互作用，以及（）设计新的遗传方法来探索胁迫和病原体反应，在这些反应中，精确的转录控制可能会产生更精确的可测试假设，以克服它们明显的功能冗余。
