Phua Su Y, Yan Dawei, Chan Kai X, Estavillo Gonzalo M, Nambara Eiji, Pogson Barry J
ARC Centre of Excellence in Plant Energy Biology, Research School of Biology, The Australian National University, Canberra, ACT, Australia.
VIB Center for Plant Systems Biology, Ghent, Belgium.
Front Plant Sci. 2018 Aug 8;9:1171. doi: 10.3389/fpls.2018.01171. eCollection 2018.
Plant growth and development are dependent on chloroplast development and function. Constitutive high level accumulation of a chloroplast stress signal, 3'-phosphoadenosine-5'-phosphate (PAP), confers drought tolerance to plants, but slow downs and alters plant growth and development. PAP, a by-product of sulfur metabolism, is maintained at very low levels by the SAL1 phosphatase during vegetative growth of and accumulates in rosettes during drought and excess light. Eight independent forward genetic screens in identified SAL1 as the regulator of multiple phenotypes related to stress responses, hormonal signaling and/or perception. In this perspective article, we collate all the phenotypes published in the past two decades, and distill the different pathways affected. Our meta-analysis of publicly available microarray data coupled to preliminary hormonal treatment and profiling results on indicate that homeostasis and responses to multiple hormones in are altered during rosette growth, suggesting a potential connection between SAL1-PAP stress retrograde pathway and hormonal signaling. We propose the SAL1-PAP pathway as a case study for integrating chloroplast retrograde signaling, light signaling and hormonal signaling in plant growth and morphogenesis.
植物的生长和发育依赖于叶绿体的发育及功能。叶绿体胁迫信号3'-磷酸腺苷-5'-磷酸（PAP）的组成型高水平积累赋予植物耐旱性，但会减缓并改变植物的生长和发育。PAP是硫代谢的副产物，在拟南芥营养生长期间由SAL1磷酸酶维持在极低水平，并在干旱和强光期间在莲座叶中积累。在拟南芥中进行的八项独立正向遗传筛选确定SAL1是与胁迫反应、激素信号传导和/或感知相关的多种表型的调节因子。在这篇观点文章中，我们整理了过去二十年发表的所有拟南芥表型，并提炼出受影响的不同途径。我们对公开可用的拟南芥微阵列数据进行的荟萃分析，结合对拟南芥的初步激素处理和分析结果表明，在莲座叶生长期间，拟南芥中多种激素的稳态和反应发生了改变，这表明SAL1-PAP胁迫逆向途径与激素信号传导之间存在潜在联系。我们提出将SAL1-PAP途径作为一个案例研究，以整合叶绿体逆向信号传导、光信号传导和激素信号传导在植物生长和形态发生中的作用。
