Silencing a Simple Extracellular Leucine-Rich Repeat Gene OsI-BAK1 Enhances the Resistance of Rice to Brown Planthopper Nilaparvata lugens
Many plant proteins with extracellular leucine-rich repeat (eLRR) domains play an important role in plant immunity. However, the role of one class of eLRR plant proteins—the simple eLRR proteins—in plant defenses against herbivores remains largely unknown. Here, we found that a simple eLRR protein OsI-BAK1 in rice localizes to the plasma membrane. Its expression was induced by mechanical wounding, the infestation of gravid females of brown planthopper (BPH)Nilaparvata lugensor white-backed planthopperSogatella furciferaand treatment with methyl jasmonate or abscisic acid. SilencingOsI-BAK1(ir-ibak1) in rice enhanced the BPH-induced transcript levels of three defense-related WRKY genes (OsWRKY24,OsWRKY53andOsWRKY70) but decreased the induced levels of ethylene. Bioassays revealed that the hatching rate was significantly lower in BPH eggs laid on ir-ibak1plants than wild-type (WT) plants; moreover, gravid BPH females preferred to oviposit on WT plants over ir-ibak1plants. The exogenous application of ethephon on ir-ibak1plants eliminated the BPH oviposition preference between WT and ir-ibak1plants but had no effect on the hatching rate of BPH eggs. These findings suggest that OsI-BAK1 acts as a negative modulator of defense responses in rice to BPH and that BPH might exploit this modulator for its own benefit.Keywords:rice;OsI-BAK1;Nilaparvata lugens;ethylene;plant defense responses;simple extracellular leucine-rich repeat protein
危险品化学品经营许可证（带存储）