Molecular Therapy
Volume 31, Issue 6, 7 June 2023, Pages 1675-1687
Journal home page for Molecular Therapy

Original Article
Pseudoknot-targeting Cas13b combats SARS-CoV-2 infection by suppressing viral replication

https://doi.org/10.1016/j.ymthe.2023.03.018Get rights and content

CRISPR-Cas13-mediated viral genome targeting is a novel strategy for defending against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. Here, we generated mRNA-encoded Cas13b targeting the open reading frame 1b (ORF1b) region to effectively degrade the RNA-dependent RNA polymerase gene. Of the 12 designed CRISPR RNAs (crRNAs), those targeting the pseudoknot site upstream of ORF1b were found to be the most effective in suppressing SARS-CoV-2 propagation. Pseudoknot-targeting Cas13b reduced expression of the spike protein and attenuated viral replication by 99%. It also inhibited the replication of multiple SARS-CoV-2 variants, exhibiting broad potency. We validated the therapeutic efficacy of this system in SARS-CoV-2-infected hACE2 transgenic mice, demonstrating that crRNA treatment significantly reduced viral titers. Our findings suggest that the pseudoknot region is a strategic site for targeted genomic degradation of SARS-CoV-2. Hence, pseudoknot-targeting Cas13b could be a breakthrough therapy for overcoming infections by SARS-CoV-2 or other RNA viruses.

Keywords

anti-SARS-CoV-2 drug
viral frameshifting site
pseudoknot region
mRNA-encoded CRISPR-Cas13 system

Cited by (0)

6

These authors contributed equally

View Abstract