TY - JOUR T1 - Distinctive Roles of Furin and TMPRSS2 in SARS-CoV-2 Infectivity. AU - Essalmani,Rachid, AU - Jain,Jaspreet, AU - Susan-Resiga,Delia, AU - Andréo,Ursula, AU - Evagelidis,Alexandra, AU - Derbali,Rabeb Mouna, AU - Huynh,David N, AU - Dallaire,Frédéric, AU - Laporte,Mélanie, AU - Delpal,Adrien, AU - Sutto-Ortiz,Priscila, AU - Coutard,Bruno, AU - Mapa,Claudine, AU - Wilcoxen,Keith, AU - Decroly,Etienne, AU - Nq Pham,Tram, AU - Cohen,Éric A, AU - Seidah,Nabil G, Y1 - 2022/03/28/ PY - 2022/3/29/pubmed PY - 2022/4/30/medline PY - 2022/3/28/entrez KW - Calu-3 cells KW - HeLa cells KW - SARS-CoV-2 KW - TMPRSS2 KW - cell-to-cell fusion KW - furin KW - spike KW - viral entry KW - viral infection SP - e0012822 EP - e0012822 JF - Journal of virology JO - J Virol VL - 96 IS - 8 N2 - The spike protein (S) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) directs infection of the lungs and other tissues following its binding to the angiotensin-converting enzyme 2 (ACE2) receptor. For effective infection, the S protein is cleaved at two sites: S1/S2 and S2'. The "priming" of the surface S protein at S1/S2 (PRRAR685↓) [the underlined basic amino acids refer to critical residues needed for the furin recognition] by furin has been shown to be important for SARS-CoV-2 infectivity in cells and small-animal models. In this study, for the first time we unambiguously identified by proteomics the fusion activation site S2' as KPSKR815↓ (the underlined basic amino acids refer to critical residues needed for the furin recognition) and demonstrated that this cleavage was strongly enhanced by ACE2 engagement with the S protein. Novel pharmacological furin inhibitors (BOS inhibitors) effectively blocked endogenous S protein processing at both sites in HeLa cells, and SARS-CoV-2 infection of lung-derived Calu-3 cells was completely prevented by combined inhibitors of furin (BOS) and type II transmembrane serine protease 2 (TMPRSS2) (camostat). Quantitative analyses of cell-to-cell fusion and S protein processing revealed that ACE2 shedding by TMPRSS2 was required for TMPRSS2-mediated enhancement of fusion in the absence of S1/S2 priming. We further demonstrated that the collectrin dimerization domain of ACE2 was essential for the effect of TMPRSS2 on cell-to-cell fusion. Overall, our results indicate that furin and TMPRSS2 act synergistically in viral entry and infectivity, supporting the combination of furin and TMPRSS2 inhibitors as potent antivirals against SARS-CoV-2. IMPORTANCE SARS-CoV-2, the etiological agent of COVID-19, has so far resulted in >6.1 million deaths worldwide. The spike protein (S) of the virus directs infection of the lungs and other tissues by binding the angiotensin-converting enzyme 2 (ACE2) receptor. For effective infection, the S protein is cleaved at two sites: S1/S2 and S2'. Cleavage at S1/S2 induces a conformational change favoring the S protein recognition by ACE2. The S2' cleavage is critical for triggering membrane fusion and virus entry into host cells. Our study highlights the complex dynamics of interaction between the S protein, ACE2, and the host proteases furin and TMPRSS2 during SARS-CoV-2 entry and suggests that the combination of a nontoxic furin inhibitor with a TMPRSS2 inhibitor significantly reduces viral entry in lung cells, as evidenced by an average synergistic ∼95% reduction of viral infection. This represents a powerful novel antiviral approach to reduce viral spread in individuals infected by SARS-CoV-2 or future related coronaviruses. SN - 1098-5514 UR - https://www.unboundmedicine.com/medline/citation/35343766/Distinctive_Roles_of_Furin_and_TMPRSS2_in_SARS_CoV_2_Infectivity_ DB - PRIME DP - Unbound Medicine ER -