摘要：SummaryPost-translational modifications (PTMs), such as glycosylation and palmitoylation, are critical to protein folding, stability, intracellular trafficking, and function. Understanding regulation of PTMs of SARS-CoV-2 spike (S) protein could help the therapeutic drug design. Herein, the VSV vector was used to produce SARS-CoV-2 S pseudoviruses to examine the roles of the611LYQD614and cysteine-rich motifs in S protein maturation and virus infectivity. Our results show that611LY612mutation alters S protein intracellular trafficking and reduces cell surface expression level. It also changes S protein glycosylation pattern and decreases pseudovirus infectivity. The S protein contains four cysteine-rich clusters with clusters I and II as the main palmitoylation sites. Mutations of clusters I and II disrupt S protein trafficking from ER-to-Golgi, suppress pseudovirus production, and reduce spike-mediated membrane fusion activity. Taken together, glycosylation and palmitoylation orchestrate the S protein maturation processing and are critical for S protein-mediated membrane fusion and infection.Graphical abstractDisplay OmittedHighlights•611LY612mutation alters the glycosylation pattern of the SARS-CoV-2 S protein•611LY612mutation reduces S protein surface expression level•Palmitoylation targets mature S protein to the Golgi and plasma membrane•Palmitoylation is required for pseudovirus and SARS-CoV-2 productionBiochemistry; Virology; Cell biology.
