A Hemagglutin (HA) Tag was inserted 3 in frame with the unique TGR5 exon after stop codon removal in order to generate a tagged TGR5 protein, and a tandem Tomato (Tdt) Tag was inserted downstream an IRES sequence in order to use Tdt expression as a surrogate marker for TGR5 expression. Further details were not specified. (J:313904)