Scientists of the Massachusetts Institute of Technology showed that the SARS-COV-2 coronavirus is able to embed its own genetic information in the gene of an infected cell through reverse transcription. As a result, the cell produces chimeric transcripts, which explains why recovery patients identify viral RNA. The opening is reported in the article published in the Journal Proceedings of the National Academy of Sciences.
Researchers have shown that, although SARS-COV-2 is not a retrovirus, it has the opportunity to embed a DNA copy of its RNA sequences in the human cell genome. It was discovered that the non-rings of the RNA virus are present in the genomes of many vertebrate species, including a person. As a result, the cells are able to produce chimeric RNA molecules, in which there are fragments of the virus.
Scientists revealed such signs of reverse transcription, as DNA repeats, at the ends of which are the virus sequences and sequences, which are recognized by the endonuclease Line-1 – an enzyme that splits communication in DNA. Thus, the embedding of genetic viral information occurs through a retrotransposon, belonging to class Line-1. Retrotransposon is a mobile genetic element capable of spreading by the genome of the body through copying and insert. It is believed that Retrotransposons class Line-1 make up more than 20 percent of the human genome.
According to researchers, the integration and transcription of viral sequences explains the identification of viral RNA using PCR in already recovered patients. These fragments are not capable of forming new viruses, but it is not clear whether they have any biological activity that contributes to post-person syndrome.