Arabidopsis thaliana PAD4 encodes a lipase-like gene that is important for salicylic acid signaling
Arabidopsis thaliana PAD4 encodes a lipase-like gene that is important for salicylic acid signaling
复制标题
DOI：
10.1073/pnas.96.23.13583
复制
发表时间：
1999-11-09
影响因子：
11.1
通讯作者：
Glazebrook, J
中科院分区：
文献类型：
--
作者：
Jirage, D;Tootle, TL;Glazebrook, J
拟南芥PADI基因先前被发现是多种防御反应的表达所必需的，包括响应于细菌病原体假单胞菌斑点致病菌（Pseudomonasarabingae pv）感染的camalexin合成和PR-1基因表达。本文报道了PAD 4的分离纯化，预测的PAD 4蛋白序列显示与三酰基甘油脂肪酶和其他酯酶的相似性，发现PAD 4转录本在P. erichingae感染或水杨酸（SA）处理后积累。在感染的pad 4突变体中，PAD 4转录水平非常低。SA处理诱导pad 4 -1、pad 4 -3和pad 4 -4植物中PAD 4 mRNA的表达，但不诱导pad 4 -2植物中PAD 4 mRNA的表达。PAD 4表达的诱导由P. lingae是独立的调节因子NPR 1，但诱导SA是NPR 1依赖性的。与先前观察到的pad 4突变体在病原体感染后SA积累方面存在缺陷一起，这些结果表明PAD 4参与了增加SA水平的正调控环，从而激活SA依赖性防御反应。
The Arabidopsis PADI gene previously was found to be required for expression of multiple defense responses including camalexin synthesis and PR-I gene expression in response to infection by the bacterial pathogen Pseudomonas syringae pv, maculicola. This report describes the isolation of PAD4, The predicted PAD4 protein sequence displays similarity to triacyl glycerol lipases and other esterases, The PAD4 transcript was found to accumulate after P. syringae infection or treatment with salicylic acid (SA). PAD4 transcript levels were very low in infected pad4 mutants. Treatment with SA induced expression of PAD4 mRNA in pad4-1, pad4-3, and pad4-4 plants but not in pad4-2 plants. Induction of PAD4 expression by P, syringae was independent of the regulatory factor NPR1 but induction by SA was NPR1-dependent. Taken together with the previous observation that pad4 mutants have a defect in accumulation of SA upon pathogen infection, these results suggest that PAD4 participates in a positive regulatory loop that increases SA levels, thereby activating SA-dependent defense responses.