Research and Development, DuPont Pioneer, Johnston, Iowa, United States of America.
Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa, United States of America.
PLoS One. 2018 Sep 5;13(9):e0203160. doi: 10.1371/journal.pone.0203160. eCollection 2018.
RNA interference (RNAi)-based technology shows great potential for use in agriculture, particularly for management of costly insect pests. In the decade since the insecticidal effects of environmentally-introduced RNA were first reported, this treatment has been applied to several types of insect pests. Through the course of those efforts, it has become apparent that different insects exhibit a range of sensitivity to environmentally-introduced RNAs. The variation in responses across insect is not well-understood, with differences in the underlying RNAi mechanisms being one explanation. This study evaluates eight proteins among three agricultural pests whose responses to environmental RNAi are known to differ: western corn rootworm (Diabrotica virgifera virgifera), fall armyworm (Spodoptera frugiperda), and southern green stink bug (Nezara viridula). These proteins have been identified in various organisms as centrally involved in facilitating the microRNA- and small interfering-RNA-mediated interference responses. Various bioinformatics tools, as well as gene expression profiling, were used to identify and evaluate putative homologues for characteristics that may contribute to the differing responses of these insects, such as the absence of critical functional domains within expressed sequences, the absence of entire gene sequences, or unusually low or undetectable expression of critical genes. Though many similarities were observed, the number of isoforms and expression levels of double-stranded RNA-binding and argonaute proteins varied across insect. Differences among key RNAi machinery genes of these three pests may impact the function of their RNAi pathways, and therefore, their respective responses to exogenous RNAs.
RNA 干扰（RNAi）技术在农业中具有很大的应用潜力，特别是在防治昂贵的虫害方面。自首次报道环境中引入的 RNA 具有杀虫作用以来的十年中，这种处理方法已应用于几种类型的虫害。在这些努力的过程中，很明显不同的昆虫对环境中引入的 RNA 表现出不同的敏感性。昆虫对 RNAi 的反应的变化尚不清楚，RNAi 机制的差异是一个解释。本研究评估了三种农业害虫中的八种蛋白质，已知它们对环境 RNAi 的反应不同：西部玉米根虫（Diabrotica virgifera virgifera）、秋粘虫（Spodoptera frugiperda）和南方绿臭虫（Nezara viridula）。这些蛋白质在各种生物体中被鉴定为中央参与促进 microRNA 和小干扰 RNA 介导的干扰反应。各种生物信息学工具以及基因表达谱分析用于鉴定和评估可能导致这些昆虫不同反应的特征的假定同源物，例如表达序列中关键功能域的缺失、整个基因序列的缺失或关键基因的异常低表达或无法检测。尽管观察到许多相似之处，但双螺旋 RNA 结合和 Argonaute 蛋白的同工型数量和表达水平在昆虫间存在差异。这三种害虫的关键 RNAi 机制基因之间的差异可能会影响其 RNAi 途径的功能，从而影响它们对外源 RNA 的各自反应。
