RACK1 functions in rice innate immunity by interacting with the rac1 immune complex
RACK1 functions in rice innate immunity by interacting with the rac1 immune complex
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DOI：
10.1105/tpc.107.054395
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发表时间：
2008-08-01
期刊：
影响因子：
11.6
通讯作者：
Shimamoto, Ko
中科院分区：
文献类型：
--
作者：
Nakashima, Ayako;Chen, Letian;Shimamoto, Ko
Rac 1是一个小的GTdR，作为一个调控蛋白复合体的一部分，在水稻天然免疫中起着关键作用。在这里，我们使用亲和柱层析来鉴定水稻RACK 1（活化C-激酶1受体）作为与Rac 1的相互作用物。RACK 1在多种哺乳动物信号传导途径中发挥作用，并参与植物的激素信号传导和发育。水稻含有两个RACK 1基因，RACK 1A和RACK 1B，RACK 1A蛋白与Rac 1的GTP形式相互作用。Rac 1在转录水平和转录后水平均对RACK 1A具有正调控作用。RACK 1A转录也诱导真菌诱导子和脱落酸，茉莉酸，和生长素。对转基因水稻植株和细胞培养物的分析表明，RACK 1A在活性氧（ROS）的产生和抗稻瘟病感染中起作用。过量表达RACK 1A增强水稻幼苗中活性氧的产生RACK 1A被证明与NADPH氧化酶、RAR 1和SGT 1的N末端相互作用，这些是植物抗病性的关键调节因子。这些结果表明RACK 1A通过与Rac 1免疫复合物中的多种蛋白相互作用而在水稻先天免疫中发挥作用。
A small GTPase, Rac1, plays a key role in rice (Oryza sativa) innate immunity as part of a complex of regulatory proteins. Here, we used affinity column chromatography to identify rice RACK1 (for Receptor for Activated C-Kinase 1) as an interactor with Rac1. RACK1 functions in various mammalian signaling pathways and is involved in hormone signaling and development in plants. Rice contains two RACK1 genes, RACK1A and RACK1B, and the RACK1A protein interacts with the GTP form of Rac1. Rac1 positively regulates RACK1A at both the transcriptional and posttranscriptional levels. RACK1A transcription was also induced by a fungal elicitor and by abscisic acid, jasmonate, and auxin. Analysis of transgenic rice plants and cell cultures indicates that RACK1A plays a role in the production of reactive oxygen species (ROS) and in resistance against rice blast infection. Overexpression of RACK1A enhances ROS production in rice seedlings. RACK1A was shown to interact with the N terminus of NADPH oxidase, RAR1, and SGT1, key regulators of plant disease resistance. These results suggest that RACK1A functions in rice innate immunity by interacting with multiple proteins in the Rac1 immune complex.