RNAi‐based genetically engineered rice resistant to black‐streaked dwarf virus does not show adverse genetic effects: A multi‐omics analysis

Abstract

Societal Impact Statement Advancements in science and technology enable us to address the challenges of the times: hunger, malnutrition, climate change, and dwindling natural resources. One of the most significant innovations in food and agriculture is the advent of genetic engineering, which may help us address the aforementioned challenges. Millions of people could benefit from the application of genetically engineered crops in agriculture and food. However, it is vital that biosafety assessments of unintended effects are carried out to identify any potential risks to humans, the environment, or society. Summary The study compared the extent of siRNA, transcriptomic and metabolomic changes in the leaves of four RNAi‐based genetically engineered rice lines to evaluate whether RNAi‐based genetically engineered rice that is resistant to black‐streaked dwarf virus experiences changes not seen in the non‐genetically engineered counterpart. siRNA, transcriptome, and metabolome profiling were conducted. siRNAs with different lengths and abundance were highly enriched in the transcript of rice; however, relative expression analysis of eight potential off‐target genes revealed that there was no decrease in gene expression in the RNAi‐based genetically engineered lines, meaning that no off‐target phenomena were caused as a result of siRNA derived from invert repeat sequences of rice black‐streaked dwarf virus in this study. This study identified some differentially expressed genes and differentially accumulated metabolites in the RNAi‐based genetically engineered lines; however, they were not enriched in pathways detrimental for humans, animals and the environment. Only 30 differentially expressed genes were significantly enriched in the plant hormone signal transduction pathway via a combined analysis using two‐way orthogonal partial least squares model. These genes belonging to salicylic acid, jasmonic acid, cytokinin, abscisic acid, and brassinosteroid pathway involved in pathways related to virus resistance or infection response were significantly changed. Taken together, there was no off‐target in RNAi‐based genetically engineered rice lines and may have a positive effect on virus resistance overall in this study.

Keywords

• combined analysis
• metabolome
• RNAi‐based genetically engineered rice
• siRNA
• transcriptome
• unintended effect