The cytosolic tail containing a conserved endocytosis short linear motif had been demonstrated to play a role in SARS-CoV-S protein-induced shedding of ACE2 (see Section 9), TNF-α production and SARS-CoV infection [135,136] although a combined in silico and in vitro study strengthened by confocal imaging denied any role for C-terminal tail of ACE2 in SARS-CoV and SARS-CoV-2 cell entry [137]. This evidence concerns the gene ACE2 and severe acute respiratory syndrome.