Transgenic refractory Aedes aegypti lines are resistant to multiple serotypes of dengue virus

Wei-Liang Liu,Cheng-Kang Tang,Shih-Peng Chan,Omar S Akbari,Jian-Chiuan Li,Shih-Hsun Ko,Chun-Hong Chen,Matthew P Su,Hsing-Han Li,Pei-Shi Yen,Zing Tsung-Yeh Tsai,Lie Cheng,Anna-Bella Failloux,Huai-Kuang Tsai,Chia-Wei Hsu

doi:10.1038/s41598-021-03229-4

Abstract

The areas where dengue virus (DENV) is endemic have expanded rapidly, driven in part by the global spread of Aedes species, which act as disease vectors. DENV replicates in the mosquito midgut and is disseminated to the mosquito’s salivary glands for amplification. Thus, blocking virus infection or replication in the tissues of the mosquito may be a viable strategy for reducing the incidence of DENV transmission to humans. Here we used the mariner Mos1 transposase to create an Aedes aegypti line that expresses virus-specific miRNA hairpins capable of blocking DENV replication. These microRNA are driven by the blood-meal-inducible carboxypeptidase A promoter or by the polyubiquitin promoter. The transgenic mosquitoes exhibited significantly lower infection rates and viral titers for most DENV serotypes 7 days after receiving an infectious blood meal. The treatment was also effective at day 14 post infection after a second blood meal had been administered. In viral transmission assay, we found there was significantly reduced transmission in these lines. These transgenic mosquitoes were effective in silencing most of the DENV genome; such an approach may be employed to control a dengue fever epidemic.

Highlights

The areas where dengue virus (DENV) is endemic have expanded rapidly, driven in part by the global spread of Aedes species, which act as disease vectors
All antiviral miRNA clusters were constructed in an effort to place them under the Ae. aegypti polyubiquitin (AePUB) or Ae. aegypti carboxypeptidase A (AeCPA) gene promoters to elicit either constitutive or blood-mealinducible midgut-specific expression of the effector molecules
The enhanced green fluorescent protein (EGFP) reporter was driven by the 3 × P3 promoter expressed in the eyes or anal papillae of transgenic larvae lines (Fig. 1d).Several transgenic lines were selected according to miRNA expression level

Summary

Introduction

The areas where dengue virus (DENV) is endemic have expanded rapidly, driven in part by the global spread of Aedes species, which act as disease vectors. Blocking virus infection or replication in the tissues of the mosquito may be a viable strategy for reducing the incidence of DENV transmission to humans. We used the mariner Mos[1] transposase to create an Aedes aegypti line that expresses virus-specific miRNA hairpins capable of blocking DENV replication. These microRNA are driven by the blood-meal-inducible carboxypeptidase A promoter or by the polyubiquitin promoter. We found there was significantly reduced transmission in these lines These transgenic mosquitoes were effective in silencing most of the DENV genome; such an approach may be employed to control a dengue fever epidemic. Such effector genes can help prevent the relevant disease, and gene-drive technology can be used to drive the introgression of these genes into a population of Ae. aegypti, replacing the disease-competent population with a refractory one

Methods

Results

Conclusion