ABSTRACT
I performed whole-genome sequencing on SARS-CoV-2 collected from COVID-19 samples at Mayo Clinic Rochester in mid-April, 2020, generated 85 consensus genome sequences and compared them to other genome sequences collected worldwide. I proposed a novel illustrating method using a 2D map to display populations of co-occurring nucleotide variants for intra- and inter- viral clades. This method is highly advantageous for the new era of big-data when high-throughput sequencing is becoming readily available. Using this method, I revealed the emergence of inter-clade hybrid SARS-CoV-2 lineages that are potentially caused by homologous genetic recombination.
Subject(s)
COVID-19ABSTRACT
The coronavirus disease 2019 pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an ongoing global public crisis. Although viral RNA modification has been reported based on the transcriptome architecture, the types and functions of RNA modification are still unknown. In this study, we evaluated the roles of RNA N6-methyladenosine (m6A) modification in SARS-CoV-2. Our methylated RNA immunoprecipitation sequencing (MeRIP-Seq) analysis showed that SARS-CoV-2 RNA contained m6A modification. Moreover, SARS-CoV-2 infection not only increased the expression of methyltransferase-like 3 (METTL3) but also altered its distribution. Modification of METTL3 expression by short hairpin RNA or plasmid transfection for knockdown or overexpression, respectively, affected viral replication. Furthermore, the viral key protein RdRp interacted with METTL3, and METTL3 was distributed in both the nucleus and cytoplasm in the presence of RdRp. RdRp appeared to modulate the sumoylation and ubiquitination of METTL3 via an unknown mechanism. Taken together, our findings demonstrated that the host m6A modification complex interacted with viral proteins to modulate SARS-CoV-2 replication.