Induction of RNAi Core Machinery's Gene Expression by Exogenous dsRNA and the Effects of Pre-exposure to dsRNA on the Gene Silencing Efficiency in the Pea Aphid (Acyrthosiphon pisum)

Chao Ye; Xin An; Yi-Di Jiang; Bi-Yue Ding; Feng Shang; Olivier Christiaens; Clauvis Nji Tizi Taning; Guy Smagghe; Jinzhi Niu; Jin-Jun Wang

doi:10.3389/fphys.2018.01906

Induction of RNAi Core Machinery's Gene Expression by Exogenous dsRNA and the Effects of Pre-exposure to dsRNA on the Gene Silencing Efficiency in the Pea Aphid (Acyrthosiphon pisum)

Front Physiol. 2019 Jan 9:9:1906. doi: 10.3389/fphys.2018.01906. eCollection 2018.

Authors

Chao Ye^{1

2}, Xin An^{1

2}, Yi-Di Jiang^{1

2}, Bi-Yue Ding^{1

2}, Feng Shang^{1

2}, Olivier Christiaens³, Clauvis Nji Tizi Taning³, Guy Smagghe^{1

2

3}, Jinzhi Niu^{1

2}, Jin-Jun Wang^{1

2}

Affiliations

¹ Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing, China.
² Academy of Agricultural Sciences, Southwest University, Chongqing, China.
³ Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.

Abstract

The pea aphid, Acyrthosiphon pisum, is an important agricultural pest and biological model organism, and RNA interference (RNAi) is an important tool for functional genomics and for insect pest management. However, the efficiency of RNAi in pea aphids is variable, limiting its application in aphids. In this study, we present optimized conditions for inducing and increasing the gene silencing efficiency of RNAi in pea aphids. The optimal gene silencing of the target Aphunchback gene was achieved by injecting 600 ng double-stranded (ds) RNA, and the highest mRNA depletion rate (74%) was detected at 36 h after injection. Moreover, the same gene silencing conditions were used to achieve transcript silencing for nine different genes in the pea aphid, although the silencing efficiencies for the different genes varied. Furthermore, the pre-exposure of aphids to dsRNA (600 ng dsGFP) led to significant hunchback silencing following a secondary exposure to 60 ng of dshunchback, a dose which did not lead to gene silencing when independently injected. The information presented here can be exploited to develop more efficient RNAi bioassays for pea aphids, both as gene functional study tools and an insect pest control strategy.

Keywords: RNA interference; aphids; double-stranded RNA; hunchback; pre-exposure.