ABSTRACT
Human ACE2 receptors on cells binding to Spike(S) protein on the surface of SARS-CoV-2 may be the main cause of the viruses entering into human cells. In this article, the current situation of the research on the S protein related SARS-CoV-2 infection and its mechanisms were summarized. We focused on the effect of structure of S protein on the infection, the binding sites of S proteins on ACE2 receptors in various tissues and other proteins which may regulate the process of binding, in order to elucidate the mechanisms of the infection of SARS-CoV-2. The variation of the gene of S protein can affect the transmission and virulence of SARS-CoV-2, which may give some useful references to the comprehensive understanding of the new virus of SARS-CoV-2.