Video showing the internalization of VLP-Wuhan:(E, S, N, M&M-pHluorin) into VeroE6 cells. pHluorin emits bright fluorescent light in pH≥8 but its intensity sharply decreases at pH<7.5, completely disappearing at pH<5.As the M protein C-terminal domain lies inside the VLPs, the fused pHluorin serves as a real-time indicator of the intra-VLP pH. When added to the medium (pH8), pHluorin-labelled VLPs emitted a bright green signal. However, shortly after binding to the membrane of the cells, the intensity rapidly decreased.

VeroE6

VeroE6 cells were isolated from kidney epithelial cells extracted from an African green monkey (Chlorocebus sp.)

mCherry cell labelling,

Freely diffusable mCherry.

SARS-CoV-2 VLPs Wuhan

Wild Type SARS-CoV-2 virus-like particles containing all the structural proteins.

M-pHluorin,

The Membrane protein of the VLP is labelled via pHluorin.

No treatment