RESUMO
Coronaviruses are positive-stranded RNA enveloped viruses. The helical nucleocapsid is surrounded by a lipid bilayer in which are anchored three viral proteins: the spike (S), membrane (M) and envelope (E) proteins. The M protein is the major component of the viral envelope and is believed to be its building block. The M protein of Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contains a short N-terminal domain with an N-glycosylation site. We investigated their N-glycosylation and show that polylactosamine chains are conjugated to SARS-CoV-2 and MERS-CoV M proteins in transfected and infected cells. Acidic residues present in the first transmembrane segments of the proteins are required for their glycosylation. No specific signal to specify polylactosamine conjugation could be identified and high mannose-conjugated protein was incorporated into virus-like particles.
Assuntos
COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , SARS-CoV-2/metabolismo , Proteínas da Matriz Viral/genética , Proteínas de Membrana , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismoRESUMO
Coronavirus is a large family of viruses that infect mammals and birds. Coronaviruses are known to cross barrier species and infect new ones. In the past twenty years, we witnessed the emergence of three different coronaviruses, the latest one being the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) responsible for the COVID-19 (covid disease 19) pandemic. Coronaviruses are enveloped virus with a long positive sense RNA genome. Like all viruses, they hijack the cellular machinery to replicate and produce new virions. There is no approved vaccine or specific antiviral molecule against coronaviruses but with the urgency to treat COVID-19, several candidate therapies are currently investigated.
TITLE: Les coronavirus, ennemis incertains. ABSTRACT: Les coronavirus sont une famille de virus qui infectent un grand nombre de mammifères et d'oiseaux. Cette famille de virus est connue pour sa capacité à franchir les barrières d'espèces et à en infecter de nouvelles. La pandémie actuelle de COVID-19 (coronavirus disease 19) est la conséquence de la troisième émergence de coronavirus, la plus récente, dans la population humaine depuis le début du siècle, celle du SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). Les coronavirus sont des virus enveloppés à ARN simple brin de polarité positive, qui, comme tous les virus, exploitent la machinerie cellulaire pour se multiplier. À ce jour, il n'existe aucun vaccin ni traitement antiviral spécifique pour lutter contre les coronavirus, mais plusieurs pistes thérapeutiques sont explorées pour traiter le COVID-19.