Coronavirus, binding to the host cell, protein S, ACE2 receptor. The coronavirus (in green, red and yellow), here of the SARS-COV2 type, responsible for the COVID-19 pandemic of 2020, binds to the membrane of the host cell thanks to its surface protein, protein S or spicule. The latter clings to the ACE2 receptor, the membrane receptor of the cell that will be infected. This fixation will allow the virus to introduce its encapsulated, helical RNA shown in pink in the center of the virus.