School of Electrical Engineering and Computer Science, Washington State University, PO Box 640125, Pullman, WA 99164-2752, USA.
Paul G. Allen School for Global Health, Washington State University, PO Box 647090, Pullman, WA 99164-7090, USA.
EBioMedicine. 2022 May;79:103990. doi: 10.1016/j.ebiom.2022.103990. Epub 2022 Apr 8.
The sarbecovirus subgenus of betacoronaviruses is widely distributed throughout bats and other mammals globally and includes human pathogens, SARS-CoV and SARS-CoV-2. The most studied sarbecoviruses use the host protein, ACE2, to infect cells. Curiously, the majority of sarbecoviruses identified to date do not use ACE2 and cannot readily acquire ACE2 binding through point mutations. We previously screened a broad panel of sarbecovirus spikes for cell entry and observed bat-derived viruses that could infect human cells, independent of ACE2. Here we further investigate the sequence determinants of cell entry for ACE2-independent bat sarbecoviruses.
We employed a network science-based approach to visualize sequence and entry phenotype similarities across the diversity of sarbecovirus spike protein sequences. We then verified these computational results and mapped determinants of viral entry into human cells using recombinant chimeric spike proteins within an established viral pseudotype assay.
We show ACE2-independent viruses that can infect human and bat cells in culture have a similar putative receptor binding motif, which can impart human cell entry into other bat sarbecovirus spikes that cannot otherwise infect human cells. These sequence determinants of human cell entry map to a surface-exposed protrusion from the predicted bat sarbecovirus spike receptor binding domain structure.
Our findings provide further evidence of a group of bat-derived sarbecoviruses with zoonotic potential and demonstrate the utility in applying network science to phenotypic mapping and prediction.
This work was supported by Washington State University and the Paul G. Allen School for Global Health.
β属冠状病毒的沙贝科病毒亚属广泛分布于全球蝙蝠和其他哺乳动物中，包括人类病原体 SARS-CoV 和 SARS-CoV-2。研究最多的沙贝科病毒利用宿主蛋白 ACE2 感染细胞。奇怪的是，迄今为止鉴定的大多数沙贝科病毒不使用 ACE2，并且不能通过点突变轻易获得 ACE2 结合。我们之前筛选了广泛的沙贝科病毒刺突用于细胞进入，并观察到可以感染人类细胞的源自蝙蝠的病毒，而无需 ACE2。在这里，我们进一步研究了 ACE2 非依赖性蝙蝠沙贝科病毒的细胞进入的序列决定因素。
我们采用基于网络科学的方法来可视化沙贝科病毒刺突蛋白序列多样性中的序列和进入表型相似性。然后，我们使用重组嵌合刺突蛋白在已建立的病毒假型测定中验证了这些计算结果，并映射了病毒进入人类细胞的决定因素。
我们表明，能够感染培养中的人类和蝙蝠细胞的 ACE2 非依赖性病毒具有相似的假定受体结合基序，该基序可以赋予其他不能感染人类细胞的蝙蝠沙贝科病毒刺突进入人类细胞的能力。这些人细胞进入的序列决定因素映射到预测的蝙蝠沙贝科病毒刺突受体结合域结构的表面突出物。
我们的发现进一步证明了一群具有人畜共患潜力的源自蝙蝠的沙贝科病毒，并证明了在表型映射和预测中应用网络科学的实用性。
这项工作得到了华盛顿州立大学和保罗 G. 艾伦全球健康学校的支持。
