LAUSR

Abstract CDK1 is a kind of cyclin-dependent kinases (CDKs) involved in diverse biological processes besides cell cycle regulation in various species. However, little is known about CDK1 in Nilaparvata lugens Stal (brown planthopper, BPH). In this study, the full-length cDNA of NlCDK1, a CDK1 gene in BPH, was obtained using rapid-amplification of cDNA ends (RACE) technique. RT-qPCR revealed that the expression of NlCDK1 was relatively low and stable at nymph stages from 1st star to 5th star, but increased to higher levels in gravid females 3 day to 5 day post-eclosion. Feeding-based RNA interference (RNAi) with 0.5 μg/μL dsNlCDK1 achieved an efficient knockdown of target gene expression in females after being fed with dsRNA for 6 days, and the mRNA level of NlCDK1 decreased to 19.9% in comparison with that of the dsGFP control. As a result, RNA inerference with dsNlCDK1 caused a significant decrease of the BPH survival rate to 28.0% of that for the control. RNAi of NlCDK1 also suppressed the ovarian development and significantly affected the fecundity of the females, leading to a 70.2% reduction to the number of the offspring. These data suggest that NlCDK1 is required for the ovarian development and survival of the brown planthopper.