School of Chemistry and Life Science, Advanced Institute of Materials Science, Changchun University of Technology, Changchun 130012, China.
State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan 430071, China.
ACS Nano. 2024 Oct 15;18(41):27891-27904. doi: 10.1021/acsnano.4c04212. Epub 2024 Oct 1.
Understanding the dynamic features of severe acute respiratory coronavirus 2 (SARS-CoV-2) binding to the cell membrane and entry cells is crucial for comprehending viral pathogenesis and transmission and facilitating the development of effective drugs against COVID-19. Herein, we employed atomic force microscopy (AFM)-based single-molecule force spectroscopy (SMFS) to study the binding dynamics between the virus and cell membrane. Our findings revealed that the Omicron variant of SARS-CoV-2 virus-like particles (VLPs) exhibited a slightly stronger affinity for the angiotensin-converting enzyme-2 (ACE2) receptor compared with the Delta variant and was significantly higher than the wild-type (WT). Using a real-time force-tracing technique, we quantified the dynamic parameters for a single SARS-CoV-2 VLP entry into cells, showing that approximately 200 ms and 60 pN are required. The parameters aligned with the analysis obtained from coarse-grained molecular dynamics (CGMD) simulations. Additionally, the Omicron variant invades cells at a higher entry cell speed, smaller force, and higher probability. Furthermore, single-particle fluorescence tracking visually demonstrated clathrin-dependent endocytosis for SARS-CoV-2 entry into A549 cells. The dynamic features of endocytosis provide valuable insights into the SARS-CoV-2 entry mechanism and possible intervention strategies targeting the viral infection process.
了解严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）与细胞膜结合并进入细胞的动态特征对于理解病毒发病机制和传播至关重要，也有助于开发针对 COVID-19 的有效药物。在此，我们采用原子力显微镜（AFM）的单分子力谱（SMFS）研究病毒与细胞膜之间的结合动力学。研究结果表明，与野生型（WT）相比，SARS-CoV-2 病毒样颗粒（VLPs）的奥密克戎变体与血管紧张素转化酶 2（ACE2）受体的亲和力略强，与德尔塔变体相比，其亲和力明显更高。通过实时力跟踪技术，我们定量了单个 SARS-CoV-2 VLP 进入细胞的动力学参数，表明大约需要 200ms 和 60pN。这些参数与粗粒分子动力学（CGMD）模拟分析结果一致。此外，奥密克戎变体以更高的进入细胞速度、更小的力和更高的概率侵入细胞。此外，单粒子荧光追踪直观地显示了 SARS-CoV-2 通过网格蛋白依赖的内吞作用进入 A549 细胞。内吞作用的动态特征为 SARS-CoV-2 的进入机制以及针对病毒感染过程的可能干预策略提供了有价值的见解。
