Data_Sheet_1_Simultaneous Ozone and High Light Treatments Reveal an Important Role for the Chloroplast in Co-ordination of Defense Signaling.PDF

Plants live in a world of changing environments, where they are continuously challenged by alternating biotic and abiotic stresses. To transfer information from the environment to appropriate protective responses, plants use many different signaling molecules and pathways. Reactive oxygen species (ROS) are critical signaling molecules in the regulation of plant stress responses, both inside and between cells. In natural environments, plants can experience multiple stresses simultaneously. Laboratory studies on stress interaction and crosstalk at regulation of gene expression, imply that plant responses to multiple stresses are distinctly different from single treatments. We analyzed the expression of selected marker genes and reassessed publicly available datasets to find signaling pathways regulated by ozone, which produces apoplastic ROS, and high light treatment, which produces chloroplastic ROS. Genes related to cell death regulation were differentially regulated by ozone versus high light. In a combined ozone + high light treatment, the light treatment enhanced ozone-induced cell death in leaves. The distinct responses from ozone versus high light treatments show that plants can activate stress signaling pathways in a highly precise manner.

植物生活在一个不断变化的生态环境中，它们持续面临着生物和非生物胁迫的交替挑战。为了将环境信息传递至适当的保护性响应，植物利用多种不同的信号分子和途径。活性氧（ROS）是调节植物应激反应的关键信号分子，无论是在细胞内部还是在细胞之间。在自然环境中，植物可能同时经历多种胁迫。实验室对基因表达调控中的胁迫相互作用和串扰的研究表明，植物对多种胁迫的反应与单一处理截然不同。我们分析了选定标记基因的表达，并重新评估了公开可用的数据集，以寻找由臭氧（产生细胞外ROS）和高光处理（产生叶绿体ROS）调节的信号通路。与高光处理相比，臭氧处理差异调节了与细胞死亡调控相关的基因。在臭氧加高光处理的联合处理中，光处理增强了臭氧诱导的叶片细胞死亡。臭氧处理与高光处理产生的不同反应表明，植物能够以极高的精确度激活应激信号通路。