Site Directed Mutagenesis of the Murine Coronavirus Spike Protein
Mutations were introduced in the transmembrane region of the spike protein of the murine coronavirus A59. The maturation of these mutant S proteins was not affected, they were all expressed at the cell surface, and became acylated, however some mutant S proteins did not induce cell-to-cell fusion. An I→K change in the middle of the predicted transmembrane (TM) anchor and mutation of the first three cysteine residues of the TM domain resulted in a fusion-negative phenotype. We propose a model by which these data can be explained.
KeywordsCysteine Residue Charged Residue Heptad Repeat Spike Protein Golgi Stack
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