Cryo-EM Structures Delineate a pH-Dependent Switch that Mediates Endosomal Positioning of SARS-CoV-2 Spike Receptor-Binding Domains. Zhou et al.

Supplemental Video Legends: Video S1. A side-view movie illustrating the trajectory of the 3D covariance described by eigenvector 0 in 3D variability analysis of individual spike at pH 5.5 (see Methods for a detailed description). A ratcheting motion of one NTD domain results in increased mobility of the corresponding RBD. A corresponding top view is presented in Video S2. Video S2. A top-view movie illustrating the trajectory of the 3D covariance described by eigenvector 0 in 3D variability analysis of individual spike at pH 5.5 (see Methods for a detailed description). The RBD is up and alternates between two positions. A corresponding side view is presented in Video S1. Video S3. A side-view movie illustrating the trajectory of the 3D covariance described by eigenvector 2 in 3D variability analysis of individual spike at pH 5.5 (see Methods for a detailed description). A ratcheting motion of one NTD domain results in increased mobility of the corresponding RBD. A corresponding top view is presented in Video S4. Video S4. A top-view movie illustrating the trajectory of the 3D covariance described by eigenvector 2 in 3D variability analysis of individual spike at pH 5.5 (see Methods for a detailed description). The RBD alternates between up and down positions. A corresponding side view is presented in Video S3. Video S5. pH-dependent domain movements in the SARS-CoV-2 spike and pH-switch refolding.