The Bphi008a Gene Interacts with the Ethylene Pathway and Transcriptionally Regulates MAPK Genes in the Response of Rice to Brown Planthopper Feeding
The Bphi008a Gene Interacts with the Ethylene Pathway and Transcriptionally Regulates MAPK Genes in the Response of Rice to Brown Planthopper Feeding
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DOI：
10.1104/pp.111.174334
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发表时间：
2011-06-01
期刊：
影响因子：
7.4
通讯作者：
He, Guangcun
中科院分区：
文献类型：
--
作者：
Hu, Jing;Zhou, Jiangbo;He, Guangcun
我们研究了褐飞虱诱导水稻（Oryza sativa）基因008 a（Bphi 008 a; AY 256682）增强植物对专业食草动物褐飞虱（BPH; Nilaparvata lugens）的抗性的方法。乙烯脱氢酶的表达水平和乙烯排放量的测量表明，BPH喂养迅速启动乙烯信号通路和上调Bphi 008 a转录水平后6至96小时的喂养。相反，阻断乙烯转导（使用1-甲基环丙烯）降低了由BPH喂养的野生型植物中的Bphi 008 a转录水平。体外激酶实验表明，Bphi 008 a可以被水稻促分裂原活化蛋白激酶5（OsMPK 5）磷酸化，酵母双杂交实验表明，Bphi 008 a的羧基端富含脯氨酸的区域与该激酶直接相互作用。此外，双分子荧光互补分析表明，这种相互作用发生在细胞核中。随后，我们发现Bphi 008 a在转基因植物中的上调和下调伴随着OsMPK 5、OsMPK 12、OsMPK 13和OsMPK 17转录水平的不同变化。免疫印迹分析还表明，在过量表达的植物中，OsMPK 5蛋白水平增加，而在RNA干扰植物中，在BPH喂养后，OsMPK 5蛋白水平下降。在转基因株系中，还观察到作为防御BPH的重要组成部分的几种酶的表达水平的变化。最后，酵母双杂交筛选结果显示Bphi 008 a能够与b-ZIP转录因子（OsbZIP 60）和RNA聚合酶多肽（SDRP）相互作用。
We examined ways in which the Brown planthopper induced008a (Bphi008a; AY256682) gene of rice (Oryza sativa) enhances the plant's resistance to a specialist herbivore, the brown planthopper (BPH; Nilaparvata lugens). Measurement of the expression levels of ethylene synthases and of ethylene emissions showed that BPH feeding rapidly initiated the ethylene signaling pathway and up-regulated Bphi008a transcript levels after 6 to 96 h of feeding. In contrast, blocking ethylene transduction (using 1-methylcyclopropene) reduced Bphi008a transcript levels in wild-type plants fed upon by BPH. In vitro kinase assays showed that Bphi008a can be phosphorylated by rice Mitogen-activated Protein Kinase5 (OsMPK5), and yeast two-hybrid assays demonstrated that the carboxyl-terminal proline-rich region of Bphi008a interacts directly with this kinase. Furthermore, bimolecular fluorescence complementation assays showed that this interaction occurs in the nucleus. Subsequently, we found that Bphi008a up-regulation and down-regulation were accompanied by different changes in transcription levels of OsMPK5, OsMPK12, OsMPK13, and OsMPK17 in transgenic plants. Immunoblot analysis also showed that the OsMPK5 protein level increased in overexpressing plants and decreased in RNA interference plants after BPH feeding. In transgenic lines, changes in the expression levels of several enzymes that are important components of the defenses against the BPH were also observed. Finally, yeast two-hybrid screening results showed that Bphi008a is able to interact with a b-ZIP transcription factor (OsbZIP60) and a RNA polymerase polypeptide (SDRP).