Blanco Francisca, Salinas Paula, Cecchini Nicolás M, Jordana Xavier, Van Hummelen Paul, Alvarez María Elena, Holuigue Loreto
Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago, Chile.
Plant Mol Biol. 2009 May;70(1-2):79-102. doi: 10.1007/s11103-009-9458-1. Epub 2009 Feb 7.
Salicylic acid (SA) is a stress-induced hormone involved in the activation of defense genes. Here we analyzed the early genetic responses to SA of wild type and npr1-1 mutant Arabidopsis seedlings, using Complete Arabidopsis Transcriptome MicroArray (CATMAv2) chip. We identified 217 genes rapidly induced by SA (early SAIGs); 193 by a NPR1-dependent and 24 by a NPR1-independent pathway. These two groups of genes also differed in their functional classification, expression profiles and over-representation of cis-elements, supporting differential pathways for their activation. Examination of the expression patterns for selected early SAIGs from both groups indicated that their activation by SA required TGA2/5/6 subclass of transcription factors. These genes were also activated by Pseudomonas syringae pv. tomato AvrRpm1, suggesting that they might play a role in defense against bacteria. This study gives a global idea of the early response to SA in Arabidopsis seedlings, expanding our knowledge about SA function in plant defense.
水杨酸（SA）是一种应激诱导激素，参与防御基因的激活。在此，我们使用全拟南芥转录组微阵列（CATMAv2）芯片分析了野生型和npr1-1突变体拟南芥幼苗对SA的早期基因反应。我们鉴定出217个被SA快速诱导的基因（早期SA诱导基因）；其中193个通过依赖NPR1的途径诱导，24个通过不依赖NPR1的途径诱导。这两组基因在功能分类、表达谱和顺式元件的过度表达方面也存在差异，支持了它们激活途径的差异。对两组中选定的早期SA诱导基因的表达模式进行检查表明，SA对它们的激活需要转录因子TGA2/5/6亚类。这些基因也被丁香假单胞菌番茄致病变种AvrRpm1激活，表明它们可能在抵御细菌中发挥作用。这项研究给出了拟南芥幼苗对SA早期反应的整体概念，扩展了我们对SA在植物防御中功能的认识。
