Fig. 4.

Western blot quantitation of ectopically expressed recombinant SARS-CoV-2 nucleocapsid protein in 293T cells. To evaluate N protein expression, total protein normalized lysates from 293T cells transfected with N Wuhan-Hu-1 (WT), N T205I, N D399N, N T205I/D399M, or empty vector and either 250 ng, 125 ng, or 62.5 ng of recombinant N were subjected to SDS-PAGE followed by ɑN western blot. The estimated nanograms of N loaded per lane for each variant is shown beneath the western blot determined from a standard curve generated by quantification of the commercial recombinant N standards.