The transfection efficiency was estimated to be 31 % after 24h and 36% after 48h via transfection of an empty eGFP plasmid. After transfection, cells were lysed, and proteins were extracted. The protein samples (10 µg) were subsequently separated by gel electrophoresis and probed for PTH1R, Flag-Tag and α-tubulin by Western Blot. Figure .3 shows the results of the Western Blot for both anti-PTH1R and anti-Flag-Tag with α-Tubulin (55 kDa) used as a loading control.