背景回顾：Land plants have evolved the ability to cope with submergence. Amphibious plants are adapted to both aerial and aquatic environments through phenotypic plasticity in leaf form and function, known as heterophylly. 

提出问题：In general, underwater leaves of amphibious plants are devoid of stomata, yet their molecular regulatory mechanisms remain elusive. 

主要发现：Using the emerging model of the Brassicaceae amphibious species Rorippa aquatica, we lay the foundation for the molecular physiological basis of the submergence-triggered inhibition of stomatal development. 

结果1-淹水诱导的气孔发育抑制与异叶无关：A series of temperature shift experiments showed that submergence-induced inhibition of stomatal development is largely uncoupled from morphological heterophylly and likely regulated by independent pathways.  

结果2-淹水诱导的快速转录重编程：Submergence-responsive transcriptome analysis revealed rapid reprogramming of gene expression, exemplified by the suppression of RaSPEECHLESS and RaMUTE within 1 h and the involvement of light and hormones in the developmental switch from terrestrial to submerged leaves. 

结果3-激素和光的作用：Further physiological studies place ethylene as a central regulator of the submergence-triggered inhibition of stomatal development. Surprisingly, red and blue light have opposing functions in this process: blue light promotes, whereas red light inhibits stomatal development, through influencing the ethylene pathway. Finally, jasmonic acid counteracts the inhibition of stomatal development, which can be attenuated by the red light. 

结论：The actions and interactions of light and hormone pathways in regulating stomatal development in R. aquatica are different from those in the terrestrial species, Arabidopsis thaliana. Thus, our work suggests that extensive rewiring events of red light to ethylene signaling might underlie the evolutionary adaption to water environment in Brassicaceae.

陆地植物演化出了应对淹水的能力。两栖植物通过叶形式和功能的表型可塑性（俗称异叶），能够同时适应于陆地和水下环境。通常来说，两栖植物在水下的叶片缺乏气孔，但是潜在的分子调控机制仍不清楚。利用十字花科两栖植物水生蔊菜（Rorippa aquatica）为研究对象，作者揭示了受淹水诱导的气孔发育抑制分子生理基础。一系列的温度变化试验表明，淹水诱导的气孔发育抑制在很大程度上与形态上的异叶无关，可能是由独立的途径进行调节的。淹水响应转录组分析揭示了基因表达的快速重编程，比如RaSPCH和RaMUTE基因在1小时内即被转录抑制，以及光和激素参与从叶片从陆生叶到淹水的发育转换。进一步的生理研究显示，乙烯作为淹水诱导气孔发育抑制的核心调节因子发挥作用。令人惊讶的是，红光和蓝光在这一过程中具有相反的功能，即蓝光通过影响乙烯途径促进气孔发育，而红光通过影响乙烯途径抑制气孔发育。最后，茉莉酸可以抵消气孔发育的抑制，而红光可以减弱茉莉酸的这种作用。光和激素途径在调节水生蔊菜气孔发育中的作用和相互作用与陆地植物拟南芥中的相关机制完全不同。因此，本文的研究工作表明，红光到乙烯信号转导的广泛关联可能是十字花科水生植物对水生环境适应性演化的基础。