FIG. 7.

The influence of a glycosylation signal at N⁸¹⁸ of hAPN and p6-hAPN on receptor activity for serogroup 1 coronaviruses of humans, pigs, and cats. Nucleocapsid (N) proteins (arrows) were identified by immunoblotting with goat polyclonal antisera to HCoV-229E (A) or feline polyclonal antisera to FIPV that cross-reacts with TGEV (B and C). FCWF (lane 1) or CMT93 cell lines that express wt-hAPN (lane 2), p6-hAPN (lane 3), hAPN/N818E (lane 4), p6-hAPN/N818E (lane 5), and p6-hAPN/T820E (lane 6) or cell lines created with the empty expression vector pCi-neo (lane 7) were inoculated with HCoV-229E (A), TGEV (B), or FECoV 79-1863 (C).