Viruses as a Bridge to Synthetic Genomes in Plant Biotechnology
Halima khatoon* and Dharmappa D Chavan
Published: December 28, 2022
Thanks to recent developments in genome engineering, it is now possible to make targeted changes to DNA sequences in plant cells, resulting in plants with desirable characteristics. The efficiency with which sequence-specific nucleases and repair templates are delivered to plant cells is crucial for effective gene targeting. Particle bombardment and Agrobacterium-mediated transformation are two methods that do this; however, they each change just a small percentage of cells in the tissues being treated. Vectors based on viruses that can replicate on their own have recently been shown to be an effective method of delivering GE reagents to plants. Gene targeting rates in model plants (Nicotiana benthamiana) and crops have been shown to be high for both DNA and RNA viruses (Shan.S. 2017). The use of plant viruses as vectors for the heterologous expression of genes dates back more than 30 years. Different approaches have been taken to using them since then, but what has consistently propelled viral vector use is the three-stage convergence of technology and virology tools that we will explore below. Firstly, the development of molecular biology and reverse genetics allowed for the cloning and manipulation of viral genomes to express genes of interest. The second is due to the convenience and extensive application of virus-induced gene silencing made possible by the discovery of RNA silencing and the development of high-throughput sequencing tools (Cody et al., 2019). Transient RNA and DNA replicons based on viruses provide a number of advantages over transgenic gene expression, including speed and ease of development and the potential for widespread application in a wide range of plant species. While the instability of the foreign gene in the viral genome can be problematic, these features are especially useful when rapidly increasing gene expression is a priority. Gene replacement, gene insertion, epitope presentation, the use of virus-controlled gene expression cassettes, and complementation are only some of the methods that have been tried and evaluated for foreign gene expression in various virus-based vectors (Herman B. et al. 1996). The study of host gene activities in plants and the delivery of short RNAs to insects have both benefited from the use of virus-induced gene silencing, which is RNA-mediated and activated through homology-dependent RNA degradation mechanisms (Peter A. et al. 2020).