褐飞虱（Nilaparvata lugens）是亚洲许多水稻种植区的主要迁飞性害虫。E78是核激素受体超家族的成员。E78在卵巢发育和早期胚胎发生的母体调节中起重要作用。本研究克隆了褐飞虱E78基因（NlE78），预测的氨基酸序列显示其含有两个保守结构域：NR-LBD和DBD。 定量PCR（qRT-PCR）结果显示NlE78在5龄若虫和雌成虫的卵巢中表达较高。下调NlE78的表达后，蜕皮失败率（33.2%）显著增加，且卵巢发育延迟。然而，同时下调NlE78与NlE93的表达后，羽化率显着增加（78.79%），卵巢发育情况与NlE78下调时相似但其发育并未延迟。免疫共沉淀实验表明，NlE78 与 NlE93 有蛋白-蛋白相互作用，NlE93 是已知的蜕皮激素信号通路的关键下游转录因子。通过免疫荧光进行的细胞定位实验结果发现，NlE78和NlE93均在细胞核中表达。该研究表明，NlE78 可能通过与 NlE93 的蛋白-蛋白相互作用调节卵巢发育和蜕皮。本研究对于开发基于新靶点的新型农药和新防治方法具有重要意义。

The brown planthopper, Nilaparvata lugens (Stål), is the most serious insect pest of rice. It has developed high resistance to traditional insecticides because of their intensive use. Juvenile hormone (JH) analogs have been used successfully to control this species and other pest insects. However, the molecular mechanism of JH signaling is not well understood. Krüppel-homolog 1 (Kr-h1) is a transcription factor involved in the JH pathway. In this study, the Kr-h1 cDNA was cloned and characterized from N. lugens by rapid amplification of cDNA ends (RACE) and reverse transcription PCR (RT-PCR). Its spatial and temporal expression profiles were examined by real-time quantitative PCR, and its function was also studied by RNA interference (RNAi). The open reading frame of NlKr-h1 is 1 833 bp encoding for 611 amino acids. The protein contains eight conserved zinc-finger motifs. NlKr-h1 was expressed at all life stages, with the highest mRNA level in the 4-day embryo. NlKr-h1 mRNA levels rose during each nymphal molt after the 2nd instar. In the adults, the mRNA level in males was significantly higher than that in females of either the macropterous or brachypterous type. The highest expression was observed in the female midgut. NlKr-h1 was activated by juvenile hormone III (JH III) in the 3rd-5th instar nymphs. Disruption of Nlkr-h1 expression by RNAi caused stunted wing development and malformations of both male and female external genitalia. Our findings suggest that Kr-h1 may be a useful target for pest insect management.