Mechanisms of SMXL6, 7 and 8 proteins in Arabidopsis plant adaptation to drought

本研究以拟南芥（Arabidopsis thaliana）smx 16、7、8三重突变体为材料，通过分析其耐旱表型，研究独脚金内酯信号负调控因子SMXL 6、7、8在植物耐旱性中的作用及其相关机制。我们的研究结果共同表明，SMXL 6，7和8作为耐旱性的负调节。与上述研究结果一致，独脚金内酯和karrikin受体DWARF 14（D14）和Karrikin Insensitive 2（KAI 2）分别对拟南芥的耐旱性具有正调控作用。然后，我们的目的是确定基因特异性或共同调控D14和KAI 2干旱下，使用比较分析的转录组数据的A。拟南芥D14-1和KAI 2 -2突变体在脱水条件下的生长。结果表明，在植物脱水反应中，细胞分裂素和油菜素类固醇代谢相关基因可能受D14途径的特异性调控，而光合作用、硫代葡萄糖苷和海藻糖代谢相关基因可能受D14和KAI 2途径的双重调控。

We studied the functions of the strigolactone-signaling negative regulators SMXL6,7 and 8 in drought tolerance and the associated mechanisms by analyzing the drought-tolerant phenotype of the Arabidopsis thaliana triple smxl6,7,8 mutant plants and studied several drought tolerance-related traits. Our results together indicate that the SMXL6, 7 and 8 act as negative regulators of drought tolerance. The findings of this study suggest that disruption of these SMXL genes in crops may provide a novel way to improve their drought tolerance.Consistent with the results of the above study, strigolactone and karrikin receptors, DWARF14 (D14) and KARRIKIN INSENSITIVE 2 (KAI2), respectively, have been shown to positively regulate drought tolerance in Arabidopsis. We then aimed to identify genes specifically or commonly regulated by D14 and KAI2 under drought, using comparative analysis of the transcriptome data of the A. thaliana d14-1 and kai2-2 mutants under dehydration conditions. Results suggest that some genes involved in cytokinin and brassinosteroid metabolism might be specifically regulated by the D14 pathway, whereas some genes related to photosynthesis and metabolism of glucosinolates and trehalose are potentially regulated by both D14 and KAI2 pathways in plant response to dehydration.