FIG 6.

The intracellular processing of the F protein of YLMY motif tyrosine residue mutants. (A) The effect of critical tyrosine residues on F protein cleavage efficiency. The cleavage efficiency was measured by the ratio of F₁ to F₀. (B) Analysis of the difference in YLMY tyrosine residue mutant processing with Endo H and PNGase F digestion. Mutants were used to infect BSR-T7/5 cells, and protein was collected as described above. The next steps followed the Endo H and PNGase F kit instructions. Red arrows point to lighter F protein bands. Each column and error bar represent the mean ± SD for three independent experiments.