Role of SCF ubiquitin-ligase and the COP9 signalosome in the N gene-mediated resistance response to Tobacco mosaic virus
Role of SCF ubiquitin-ligase and the COP9 signalosome in the N gene-mediated resistance response to Tobacco mosaic virus
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DOI：
10.1105/tpc.002493
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发表时间：
2002-07-01
期刊：
影响因子：
11.6
通讯作者：
Dinesh-Kumar, SP
中科院分区：
文献类型：
--
作者：
Liu, Y;Schiff, M;Dinesh-Kumar, SP
烟草N基因赋予对烟草花叶病毒（TMV）的抗性，并且编码toll-Eukin-1受体/核苷酸结合/富含Leu的重复类蛋白。最近的证据表明，本氏烟草（Nicotianabenthamiana）Rar 1基因（NbRar 1）编码一种具有锌指基序的蛋白质，称为CHORD（富含半胱氨酸和组氨酸的结构域），是N.为了研究NbRar 1在植物防御中的作用，我们确定了它的相互作用伙伴。我们发现，NbRar 1蛋白与NbSGT 1相互作用，NbSGT 1是SCIF（Skp 1/Cullin/F-box蛋白）型E3泛素连接酶复合物的高度保守组分，参与蛋白质降解。此外，我们发现NbSGT 1与NbSKP 1相互作用。NbSGT 1和NbSKP 1的抑制表明这些基因在氮介导的TMV抗性反应中发挥重要作用。NbRar 1和NbSGT 1都与COP 9信号体相关，COP 9信号体是另一种通过泛素-蛋白酶体途径参与蛋白质降解的多蛋白复合物。NbCOP 9信号体的沉默也损害了N介导的对TMV的抗性。我们的研究结果揭示了SCF和COP 9信号体在植物防御信号中的新作用。
The tobacco N gene confers resistance to Tobacco mosaic virus (TMV) and encodes a toll-interieukin-1 receptor/ nucleotide binding/Leu-rich repeat class protein. Recent evidence indicates that the Nicotiana benthamiana Rar1 gene (NbRar1), which encodes a protein with a zinc finger motif called CHORD (Cys- and His-rich domain), is required for the function of N. To investigate the role of NbRar1 in plant defense, we identified its interaction partners. We show that the NbRar1 protein interacts with NbSGT1, a highly conserved component of the SCIF (Skp1/Cullin/F-box protein)-type E3 ubiquitin ligase complex involved in protein degradation. In addition, we show that NbSGT1 interacts with NbSKP1. Suppression of NbSGT1 and NbSKP1 shows that these genes play an important role in the N-mediated resistance response to TMV. Both NbRar1 and NbSGT1 associate with the COP9 signalosome, another multiprotein complex involved in protein degradation via the ubiquitin-proteasome pathway. Silencing of the NbCOP9 signalosome also compromises N-mediated resistance to TMV. Our results reveal new roles for SCF and the COP9 signalosome in plant defense signaling.