Genoud Thierry, Buchala Antony J, Chua Nam-Hai, Métraux Jean-Pierre
Département de Biologie, Université de Fribourg, Rte A. Gockel 3, 1700 Fribourg, Switzerland.
Plant J. 2002 Jul;31(1):87-95. doi: 10.1046/j.1365-313x.2002.01338.x.
The interaction of phytochrome signalling with the SA signal transduction pathway has been investigated in Arabidopsis using single and multiple mutants affected in light perception (phyA and phyB deficient) and light-signal processing (psi2, phytochrome signalling). The induction of PR1 by SA and functional analogues has been found to strictly correlate with the activity of the signalling pathway controlled by both phyA and phyB photoreceptors. In darkness as well as dim light, and independently of a carbohydrate source, SA-induced PR gene expression as well as the hypersensitive response to pathogens (HR) are strongly reduced. Moreover, the initiation of HR also exhibits a strict dependence upon both the presence and the amplitude of a phytochrome-elicited signal. The growth of an incompatible strain of bacterial a pathogen (Pseudomonas syringae pv. tomato) was enhanced in phyA-phyB and decreased in psi2 mutants. While functional chloroplasts were found necessary for the development of an HR, the induction of PRs was strictly dependent on light, but independent of functional chloroplasts. Taken together, these data demonstrate that the light-induced signalling pathway interacts with the pathogen/SA-mediated signal transduction route. These results are summarized in a formalism that allows qualitative computer simulation.
利用在光感知（phyA和phyB缺陷）和光信号处理（psi2，光敏色素信号传导）方面受影响的单突变体和多突变体，在拟南芥中研究了光敏色素信号传导与水杨酸（SA）信号转导途径的相互作用。已发现SA及其功能类似物对PR1的诱导与由phyA和phyB光受体控制的信号传导途径的活性严格相关。在黑暗以及弱光条件下，且与碳水化合物来源无关，SA诱导的PR基因表达以及对病原体的超敏反应（HR）都大幅降低。此外，HR的启动也严格依赖于光敏色素引发信号的存在及其强度。在phyA - phyB双突变体中，一种不相容的细菌病原体（丁香假单胞菌番茄致病变种）的生长增强，而在psi2突变体中则减弱。虽然发现功能性叶绿体对于HR的发展是必需的，但PR的诱导严格依赖于光，而与功能性叶绿体无关。综上所述，这些数据表明光诱导的信号传导途径与病原体/SA介导的信号转导途径相互作用。这些结果以一种形式化方式进行了总结，从而能够进行定性的计算机模拟。
