Efficient RNA interference for three neuronally-expressed genes in Nilaparvata lugens (Stål) (Hemiptera: Delphacidae)
, 2017,20(2):513-519.
10.1016/j.aspen.2017.03.009
Abstract
In the brown planthopper Nilaparvata lugens, introduction of double-stranded RNA (dsRNA) successfully knocks down genes transcribed in several types of tissues. However, whether RNA interference (RNAi) can effectively reduce the transcripts of neuronally-expressed genes remains undetermined. In the present paper, we selected three neuronally-expressed genes respectively encoding prothoracicotropic hormone (NlPTTH), pigment-dispersing factor (NlPDF) and short neuropeptide F (NlsNPF). The transcripts of the three genes were detectable throughout all tested developmental stages, and were mainly restricted to the nervous system of N. lugens. We introduced dsRNA originated from each of the three neuronally-expressed genes at a dose of 300 ng into the nymphal body cavity by microinjection. The target mRNA was successfully knocked down. Moreover, silencing of NlPTTH downregulated the transcripts of two ecdysteroidogenesis genes (NlPHM and NlDIB), and surpressed the expression of an ecdysone-response genes (NlFTZ-F1). Furthermore, RNAi of NlPTTH caused typical 20-hydroxyecdysone deficient phenotypes: nymphal development was delayed and nymphal lethality occurred. In addition, injection of a series of dsNlsDPF solutions at the doses of 300, 60, 12, 2.4 and 0.5 ng into the fourth-instar nymphs decreased its target transcript in a dose-dependent manner: the mRNA levels reduced by 94%, 86%, 57%, 33% and 29%, respectively. Therefore, delivery of dsRNA by microinjection can effectively repress the transcripts of the neuronally-expressed genes in N. lugens.