Bactrocera dorsalis male sterilization by targeted RNA interference of spermatogenesis: empowering sterile insect technique programs.

Yong-Cheng Dong,Zhen-Zhong Chen,Anthony R Clarke,Zhi-Jian Wang,Chang-Ying Niu

doi:10.1038/srep35750

Yong-Cheng Dong, Zhen-Zhong Chen + Show 3 more

Open Access

https://doi.org/10.1038/srep35750

Copy DOI

Abstract

RNA interference (RNAi) is a genetic technique which has novel application for sustainable pest control. The Sterile Insect Technique (SIT) uses releases of mass-produced, sterile male insects to out-compete wild males for mates to reduce pest populations. RNAi sterilization of SIT males would have several advantages over radiation sterilization, but to achieve this appropriate target genes must first be identified and then targeted with interference technology. With this goal, eight spermatogenesis related candidate genes were cloned and tested for potential activity in Bactrocera dorsalis. The knockdown of candidate genes by oral delivery of dsRNAs did not influence the mating of male flies, but significantly affected the daily average number of eggs laid by females, and reduced egg hatching rate by 16–60%. RNAi negatively affected spermatozoa quantitatively and qualitatively. Following the mating of lola-/topi-/rac-/rho-/upd-/magu-silenced males, we recorded a significant decrease in number and length of spermatozoa in female spermatheca compared to gfp-silenced control group. In a greenhouse trial, the number of damaged oranges and B. dorsalis larvae were significantly reduced in a dsrho-treated group compared with the dsgfp group. This study provides strong evidence for the use RNAi in pest management, especially for the improvement of SIT against B. dorsalis and other species.

Highlights

RNA interference (RNAi) is a genetic technique which has novel application for sustainable pest control
Eight spermatogenesis related genes in B. dorsalis, namely lola, topi, per, aly, rac, rho, upd and magu, were cloned and their potentials in pest control application were evaluated by orally supplied engineered-bacteria expressing target double-stranded RNA (dsRNA)
The greenhouse cage trials proved successful for controlling B. dorsalis by feeding with bacteria expressing dsrho, which resulted in less damaged oranges and less larvae

Summary

Introduction

RNA interference (RNAi) is a genetic technique which has novel application for sustainable pest control. Species Bactrocera oleae Bactrocera oleae Bactrocera neohumeralis Bactrocera oleae Bactrocera oleae Bactrocera oleae Bactrocera oleae Bactrocera cucurbitae of factory-reared flies is almost always achieved through ionizing radiation which, while effective, is limiting because of the need for an appropriate radiation source and the unavoidable loss of competitive ability in treated male flies due to somatic damage[14,15]. These detrimental effects have prompted studies to find alternative sterilization strategies. BMP and JAK-STAT pathways execute the roles of GSCs maintenance[17], while the magu gene can modulate BMP signaling to control GSCs maintenance in the testis niche[20], and the transcriptional regulator longitudinals lacking (lola) is required for stem cell maintenance[21]

Objectives

Methods

Results

Conclusion