Functional dissection of the spike glycoprotein S1 subunit and identification of cellular cofactors for regulation of swine acute diarrhea syndrome coronavirus entry

作者：Yong‐Le Yang, Bin Wang, Wentao Li, Hou-Li Cai, Qian-Yu Qian, Qin Yu, Fang‐Shu Shi, Berend‐Jan Bosch, Yao‐Wei Huang · 发表于：Journal of Virology · 年份：2024 · DOI：10.1128/jvi.00139-24 · 被引用次数：16 · 研究领域：Viral gastroenteritis research and epidemiology、Virus-based gene therapy research、SARS-CoV-2 and COVID-19 Research

ABSTRACT Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a novel porcine enteric coronavirus, and the broad interspecies infection of SADS-CoV poses a potential threat to human health. This study provides experimental evidence to dissect the roles of distinct domains within the SADS-CoV spike S1 subunit in cellular entry. Specifically, we expressed the S1 and its subdomains, S1 A and S1 B . Cell binding and invasion inhibition assays revealed a preference for the S1 B subdomain in binding to the receptors on the cell surface, and this unknown receptor is not utilized by the porcine epidemic diarrhea virus. Nanoparticle display demonstrated hemagglutination of erythrocytes from pigs, humans, and mice, linking the S1 A subdomain to the binding of sialic acid (Sia) involved in virus attachment. We successfully rescued GFP-labeled SADS-CoV (rSADS-GFP) from a recombinant cDNA clone to track viral infection. Antisera raised against S1, S1 A , or S1 B contained highly potent neutralizing antibodies, with anti-S1 B showing better efficiency in neutralizing rSADS-GFP infection compared to anti-S1 A . Furthermore, depletion of heparan sulfate (HS) by heparinase treatment or pre-incubation of rSADS-GFP with HS or constituent monosaccharides could inhibit SADS-CoV entry. Finally, we demonstrated that active furin cleavage of S glycoprotein and the presence of type II transmembrane serine protease (TMPRSS2) are essential for SADS-CoV infection. These combined observations suggest ...