We initially constructed a tetracysteine (PG) tagged hMC4R (hMC4R-PG) for co-transfection with a variant tetracysteine (FLN) tagged hMRAPα (hMRAPα-FLN) in order for dual detection of the tetracysteine tags by biarsenical labelling with FlAsH-EDT 2 or ReAsH-EDT 2, respectively.
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