SARS-CoV-2 Produces a microRNA, CoV2-miR-O8, in Patients with COVID-19 Infection

Many viruses produce microRNAs (miRNAs), termed viral miRNAs (v-miRNAs), with the capacity to target host gene expression. Bioinformatic and cell culture studies suggest that SARS-CoV-2 can also generate v-miRNAs. This in vivo study defines the SARS-CoV-2 encoded small RNAs present in nasopharyngeal swabs of patients with COVID-19 infection using small RNAseq. A specific conserved sequence (CoV2-miR-O8) is defined that is not expressed in other coronaviruses but is preserved in all SARS-CoV-2 variants. CoV2-miR-O8 is highly represented in nasopharyngeal samples from patients with COVID-19 infection, is detected by RT-PCR assays in patients, has features consistent with Dicer and Drosha generation as well as interaction with Argonaute and targets specific human microRNAs.