Genetic And Functional Analysis Of Insulin Receptor Genes Of Brown Dlanthopoer(Nilaparvata Lugens)

The brown planthopper (BPH), Nilaparvata lugens (Hemiptera:Delphacidae), is a monophagous pest which only feeds and breeds on rice and common wild rice.It is the primary pests of rice in China and many other Asian countries. At present, the intensive agriculture production, unscientific use of chemical fertilizers and pesticides have caused the intermittent outbreak of BPH. Insulin signal transduction a plays major role in many important physiological processes, including growth, development, metabolism, reproduction and aging. Therefore, it is urgent to clarify the molecular mechanism of insulin signaling pathway in regulating metamorphosis, so that provide important theoretical basis for insect pest control. In this study, We cloned the NlInR1and NlInR2full-length cDNA sequences from BPH, which were5918bp (NlInR1) and6016bp (NlInR2).Predicted open reading frames (ORF) of the two sequences were4362bp and4281bp. They encode two158.4and158.9kDa proteins containing1454and1427amino acid residues respectively. To verify NlInR1and NlInR2biology function, we employed RNA interference technology,and found that NlInR1has a great influence on the growth, development and metabolism in BPH:(1) NlInR1silencing shortens the hind tibiae length of BPH by about9.2%;(2) NlInR1silencing delays BPH development, extending the duration of development stage from2nd to adult by about28%;(3) NlInR1silencing reduces the weight of5th instar nymph BPH (24h and72h after molting) about17%and16%respectively;(4) NlInR1silencing disturbed lipid metabolism in BPH, triglycerides of the5th instar nymph and female adults were increased by about35%and61%, respectively. However, knockdown of NlInR1had no obvious effect on BPH, which needs further research to understand its function.