Abstract
RNA interference (RNAi) is a powerful and convenient tool for sequence-specific gene silencing, and it is triggered by double-stranded RNA (dsRNA). RNAi can be easily achieved in many eukaryotes by either injecting or feeding dsRNAs. This mechanism has demonstrated its potential in fundamental research on genetics, medicine and agriculture. However, the possibility that insects might develop refractoriness to RNAi remains unexplored. In this study, we report that the oriental fruit fly, Bactrocera dorsalis, became refractory to RNAi using orally administered dsRNA targeting endogenous genes. Furthermore, refractoriness to RNAi is not gene-specific, and its duration depends on the dsRNA concentration. RNAi blockage requires the endocytic pathway. Fluorescence microscopy indicated that in RNAi refractory flies, dsRNA uptake is blocked. Genes involved in the entry of dsRNAs into cells, including chc, cog3, light and others, are down-regulated in RNAi refractory flies. Increasing the endocytic capacity by improving F-actin polymerization disrupts RNAi refractoriness after both primary and secondary dsRNA exposures. Our results demonstrate that an insect can become refractory to RNAi by preventing the entry of dsRNA into its cells.
Highlights
Endocytic pathway mediates refractoriness of insect Bactrocera dorsalis to RNA interference Xiaoxue Li, Xiaolong Dong, Cong Zou & Hongyu Zhang
The results showed that exposure to 92 bp and 494 bp egfp double-stranded RNA (dsRNA) did not change the effect of a secondary RNA interference (RNAi) targeting either rpl[19] or spr
Taken together, our findings indicate that B. dorsalis possesses a mechanism to down-regulate dsRNA-mediated RNAi
Summary
Endocytic pathway mediates refractoriness of insect Bactrocera dorsalis to RNA interference Xiaoxue Li, Xiaolong Dong, Cong Zou & Hongyu Zhang. Genes involved in the entry of dsRNAs into cells, including chc, cog[3], light and others, are down-regulated in RNAi refractory flies. Our results demonstrate that an insect can become refractory to RNAi by preventing the entry of dsRNA into its cells. DsRNAs can be delivered into animals by various methods, including injection[2], feeding[3] and transgenic expression[4]. R NAi is a conserved mechanism by which endogenous genes are silenced by dsRNAs in a sequence-specific manner. For the efficient use of RNAi in pest control, the focus must be on non-cell-autonomous RNAi caused by the feeding of dsRNAs9. The dsRNA molecules can pass through the intestinal cells and into the body cavity, where they can act on other tissues, such as muscles[8]
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.
