MHV genome cleavage efficiency by genome editing technology - CRISPR/Cas9

Abstract

The World Health Organization (WHO) declared at the end of January 2020 a Public Health Emergency of International Concern and subsequently a COVID19 pandemic caused by the Sars- Cov-2 virus in early March. New COVID-19 cases and deaths continued to increase, and on December 20, 2020, since the pandemic began, more than 75 million reported cases and 1.6 million deaths. The rush within hospitals increases the sense of finding an effective treatment that can significantly reduce fatalities and the most severe disease symptoms; that brings with it damage to the organism that can last for years, even for life. However, disease control may still be far from being achieved consistently. Although many drugs used as treatment are effective in vitro, none of them has been shown to be able to act effectively to reduce the damage caused by Sars-CoV-2 in initial or severe patients. Therefore, studies of different strategies are welcome to obtain more information to understand more effective targets, which can lead science and humanity to overcome this challenge. Genomic editing systems are potential tools for editing and attacking viral genomic sequences. The CRISPR-Cas9 type II system is the most widely used for genomic editing, with several variants attributing different properties to the Cas9 protein. It is mainly due to its simplicity of activation depending only on the Cas9 protein and a guide RNA. However, the widespread use of Cas9 protein for double-stranded DNA editing is the most classic CRISPR system approach. Evidence shown by Dr. Jennifer Doudna and other researchers showed that in addition to acting on double-stranded DNA, the Cas9 protein could have high affinity and action on single-stranded RNA (ssRNA) molecules. Assuming that the genetic material of Sars-CoV-2 is composed of ssRNA, and that in the case of cells infected with Sars-CoV-2 we find RNA structures from the viral genome, we hypothesized that the Cas9 system could be effective in the control of the proliferation of Sars-Cov2 virus in the infected cell by preventing the formation of the competent virus, then producing an anti-viremic activity. This project aims to verify the success of viral RNA of coronavirus cleavage by CRISPR/cas9 system with coronavirus MHV genome-specific guides. We may prove the efficiency of this system in the approach to the control of retroviral proliferation.(AU)