Arthropod Genetics, The Pirbright Institute, Pirbright, Woking GU24 0NF, United Kingdom.
Applied Virology, Institute of Technology, University of Tartu, Tartu 50411, Estonia.
Proc Natl Acad Sci U S A. 2023 Sep 12;120(37):e2303080120. doi: 10.1073/pnas.2303080120. Epub 2023 Sep 5.
Multiple viruses, including pathogenic viruses, bacteriophages, and even plant viruses, cause a phenomenon termed superinfection exclusion whereby a currently infected cell is resistant to secondary infection by the same or a closely related virus. In alphaviruses, this process is thought to be mediated, at least in part, by the viral protease (nsP2) which is responsible for processing the nonstructural polyproteins (P123 and P1234) into individual proteins (nsP1-nsP4), forming the viral replication complex. Taking a synthetic biology approach, we mimicked this naturally occurring phenomenon by generating a superinfection exclusion-like state in mosquitoes, rendering them refractory to alphavirus infection. By artificially expressing Sindbis virus (SINV) and chikungunya virus (CHIKV) nsP2 in mosquito cells and transgenic mosquitoes, we demonstrated a reduction in both SINV and CHIKV viral replication rates in cells following viral infection as well as reduced infection prevalence, viral titers, and transmission potential in mosquitoes.
多种病毒，包括致病性病毒、噬菌体，甚至植物病毒，都会引起一种被称为“超级感染排斥”的现象，即当前感染的细胞对同一或密切相关的病毒的二次感染具有抗性。在甲病毒中，这个过程至少部分是由病毒蛋白酶（nsP2）介导的，nsP2 负责将非结构多蛋白（P123 和 P1234）加工成单个蛋白（nsP1-nsP4），形成病毒复制复合物。我们采用合成生物学的方法，通过在蚊子中产生类似于超级感染排斥的状态来模拟这种自然发生的现象，使它们对甲病毒感染产生抗性。通过在蚊子细胞和转基因蚊子中人工表达辛德毕斯病毒（SINV）和基孔肯雅病毒（CHIKV）的 nsP2，我们证明了在病毒感染后，SINV 和 CHIKV 的病毒复制率以及蚊子中的感染流行率、病毒滴度和传播潜力都降低了。
