S1 Subunit and Host Proteases as Potential Therapeutic Avenues for the Treatment of COVID-19.

The novel corona virus (SARS-CoV-2) that causes severe acute respiratory syndrome, now called COVID-19 initially originated in Wuhan city of China and later spread across borders and infected more than five million people and killed over 3.4 lakh people all over the globe. This disease has been announced as pandemic by WHO. So far, there has been not much progress in terms of drug development for fighting against this deadliest virus, also no existing drugs has been reported completely effective for COVID-19 treatment owing to lack of effective therapeutic targets and a broad understanding of the viral behavior in target cell. Some reports have found and confirmed that SARS-CoV-2 like others SARS-CoVs utilizes angiotensin converting enzyme-2 receptor for making entry into target cell by binding to the receptor with its S1 subunit and employing host cell proteases for cleaving S2 subunit at S2' in order to fuse with cell membrane. Thus, simultaneous blocking of S1 subunit and inactivation of proteases seem to be promising therapeutic targets for the development of effective novel drugs. In current write up we hypothesize that S1 subunit and host proteases as potential therapeutic avenues for the treatment of COVID-19.