miRNA binding pressure channels evolution of SARS-CoV-2 genomes

In somatic cells, microRNAs (miRNAs) bind to the genomes of RNA viruses and influence their translation and replication. Here we demonstrate that a significant number of miRNA binding sites locate in the NSP4 region of the SARS-CoV-2 genome, and the intestinal human miRNAs exert evolutionary pressure on this region. Notably, in infected cells, NSP4 promotes the formation of double-membrane vesicles, which serve as the scaffolds for replication-transcriptional complexes and protect viral RNA from intracellular destruction. In three years of selection, the loss of many miRNA binding sites, in particular, those within the NSP4, has shaped the SARS-CoV-2 genomes to promote the descendants of the BA.2 variants as the dominant strains and define current momentum of the pandemics.