Abstract
Nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome P450 reductase (CPR) is an essential enzyme that transfers electrons from NADPH to cytochrome P450 monooxygenases. CPR is involved in cuticular hydrocarbon (CHC) synthesis in insects and is vital for insect development and survival. Here, we clarify the physiological function of a CPR gene in Nilaparvata lugens, an important rice pest, by using RNA interference. CPR gene knockdown leads to the functional loss of waterproofing and water retention in the integument of female adults, which causes significantly reduced body weight and a lethal phenotype. Scanning electron microscopy shows that the lipid layer on the outermost surface of the abdominal cuticle becomes thin in dsCPR-injected adults. Furthermore, CHC profile analysis reveals that CPR knockdown significantly decreases the contents of CHCs with a carbon chain length ≥ C27 in adult females. Moreover, we find that CPR knockdown generates a deficient phenotype in ovaries with deformed oocytes and a complete failure of egg-laying. These findings suggest that CPR plays multiple functional roles in CHC biosynthesis and embryo development in insects.
Highlights
Nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome P450 reductase (CPR) is a cofactor of cytochrome P450 monooxygenases (P450s) that donates electrons from NADPH to the heme center of P450s [1,2]
CPR belongs to the flavoprotein family and contains an N-terminal transmembrane region and three conserved binding domains for flavin mononucleotide (FMN), flavin adenine dinucleotide (FAD), and NADPH [3–5]
We verified that CPR is essential for waterproofing and water retention in N. lugens
Summary
Nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome P450 reductase (CPR) is a cofactor of cytochrome P450 monooxygenases (P450s) that donates electrons from NADPH to the heme center of P450s [1,2]. CPR belongs to the flavoprotein family and contains an N-terminal transmembrane region and three conserved binding domains for flavin mononucleotide (FMN), flavin adenine dinucleotide (FAD), and NADPH [3–5]. Several CPRs have been identified and characterized in insects, such as Drosophila melanogaster [6,7], Helicoverpa armigera [8], Nilaparvata lugens [9], Rhopalosiphum padi (L.) [10], Laodelphax striatellus (fallén) [11], Locusta migratoria [12], Cnaphalocrocis medinalis [12], Spodoptera Litura [13], Bemisia tabaci [14], Acyrthosiphon pisum [15], and Diaphorina citri [16]. P450 enzymes catalyze the oxidative metabolism of various endogenous and xenobiotic substrates, including insecticides, steroids, and cuticular hydrocarbons (CHCs). As cofactors of P450s, CPRs are essential for the oxidative metabolism of different substrates. It is known that CPRs are closely related to susceptibility to insecticides and CHC biosynthesis in insects [7,17]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
