Hunt M D, Neuenschwander U H, Delaney T P, Weymann K B, Friedrich L B, Lawton K A, Steiner H Y, Ryals J A
Agricultural Biotechnology Research Unit, Ciba-Geigy Corporation, Research Triangle Park, NC 27709, USA.
Gene. 1996 Nov 7;179(1):89-95. doi: 10.1016/s0378-1119(96)00429-5.
Little is known about the signal transduction events that lead to the establishment of the broad-spectrum, inducible plant immunity called systemic acquired resistance (SAR). Salicylic acid (SA) accumulation has been shown to be essential for the expression of SAR and plays a key role in SAR signaling. Hydrogen peroxide has been proposed to serve as a second messenger of SA. However, our results do not support such a role in the establishment of SAR. Further elucidation of SAR signal transduction has been facilitated by the identification and characterization of mutants. The lesions simulating disease (lsd). resistance response mutant class exhibits spontaneous lesions similar to those that occur during the hypersensitive response. Interestingly, some lsd mutants lose their lesioned phenotype when SA accumulation is prevented by expression of the nahG gene (encoding salicylate hydroxylase), thereby providing evidence for a feedback loop in SAR signal transduction. Characterization of a mutant non-responsive to SAR activator treatments has provided additional evidence for common signaling components between SAR and gene-for-gene resistance.
关于导致建立称为系统获得性抗性（SAR）的广谱、诱导型植物免疫的信号转导事件，人们了解甚少。水杨酸（SA）积累已被证明是SAR表达所必需的，并且在SAR信号传导中起关键作用。过氧化氢已被认为是SA的第二信使。然而，我们的结果并不支持其在SAR建立中的这种作用。突变体的鉴定和表征促进了对SAR信号转导的进一步阐明。模拟疾病损伤（lsd）抗性反应突变体类别表现出与过敏反应期间出现的损伤相似的自发损伤。有趣的是，当通过表达nahG基因（编码水杨酸羟化酶）阻止SA积累时，一些lsd突变体失去其损伤表型，从而为SAR信号转导中的反馈环提供了证据。对一种对SAR激活剂处理无反应的突变体的表征为SAR和基因对基因抗性之间的共同信号成分提供了额外证据。
