Fig. 1
From: Chronic respiratory diseases other than asthma in children: the COVID-19 tsunami
Structure of SARS-CoV-2 virion. SARS-CoV-2 belongs to the Coronaviridae family and contains a single stranded RNA genome encoding four structural proteins, namely spike (S), envelope (E), nucleocapsid (N) and membrane (M) proteins. S, E and M proteins constitute the viral coat, while N protein packages the viral genome. SARS-CoV-2 targets the host cells through S proteins, which bind to ACE-2 receptor. TMPRSS2, a type 2 transmembrane serine protease, is needed to activate S proteins for membrane fusion, enabling cell infection