A genome-wide CRISPR screen identifies host factors that regulate SARS-CoV-2 entry

Zhu, Yunkai; Feng, Fei; Hu, Gaowei; Wang, Yuyan; Yu, Yin; Zhu, Yuanfei; Xu, Wei; Cai, Xia; Sun, Zhiping; Han, Wendong; Ye, Rong; Qu, Di; Ding, Qiang; Huang, Xinxin; Chen, Hongjun; Xu, Wei; Xie, Youhua; Cai, Qiliang; Yuan, Zhenghong; Zhang, Rong

The global spread of SARS-CoV-2 is posing major public health challenges. One feature of SARS-CoV-2 spike protein is the insertion of multi-basic residues at the S1/S2 subunit cleavage site. Here, we find that the virus with intact spike (Sfull) preferentially enters cells via fusion at the plasma membrane, whereas a clone (Sdel) with deletion disrupting the multi-basic S1/S2 site utilizes an endosomal entry pathway. Using Sdel as model, we perform a genome-wide CRISPR screen and identify several endosomal entry-specific regulators. Experimental validation of hits from the CRISPR screen shows that host factors regulating the surface expression of angiotensin-converting enzyme 2 (ACE2) affect entry of Sfull virus. Animal-to-animal transmission with the Sdel virus is reduced compared to Sfull in the hamster model. These findings highlight the critical role of the S1/S2 boundary of SARS-CoV-2 spike protein in modulating virus entry and transmission and provide insights into entry of coronaviruses.