Silencing of ApCht7 and ApCht10 revealed their function and evaluation of their potential as RNAi targets in Acyrthosiphon pisum.

One of the successful strategies developed for studying the gene function of aphids is to silence aphid gene expression by plant-mediated RNA interference (RNAi). In this study, we analyzed the expression patterns and the biological functions of genes related to chitin metabolism ApCht7 and ApCht10 by using gene-specific plant-mediated RNAi in the green pea aphid, Acyrthosiphon pisum (Ap). The RT-qPCR results demonstrated that the RNAi-mediated silencing of these ApChts suppressed the expression of most genes involved in the chitin degradation pathway, but enhanced the expressions of ApHK, ApGFAT, ApPGM and ApCHS, indicating that the RNAi of ApChts could affect the expression of genes related to chitin metabolism and regulate the chitin metabolism. Furthermore, it resulted in a decrease in aphid body weight of aphids, with mortality rates ranging from 3.3 to 26.1%. Abnormal phenotypes (e.g., molting defect and wrinkled integument) were observed in the treated nymphs, leading to early lethality. The aphid reproduction rate reduced by 27.9–40.5% at 120 h after RNAi of ApChts. The target genes ApCht7 and ApCht10 expression were also downregulated in the progeny nymphs born from the mothers exposed to dsRNA-plants with significantly lower body weights. The previously mentioned results suggest that the effects of RNAi ApCht7 and ApCht10 are heritable and passed down to offspring. Our study provides a foundation for the practical application of the plant-mediated RNAi of ApCht7 and ApCht10 as a powerful tools and methods for controlling field aphid outbreaks. [ABSTRACT FROM AUTHOR]