Expression and localization of recombinant human B2 receptors in the methylotrophic yeast Pichia pastoris

The human bradykinin B2 receptor (B2R) fused with green fluorescent protein (GFP) at the C-terminal has been expressed in the methylotrophic yeast of Pichia pastoris. In the expression vector, B2R gene was drove under the highly inducible promoter of alcohol oxidase 1 gene of P. pastoris. By fluorescence activated cell sorting (FACS) analysis and western blot analysis, it was proved that B2R recombinant receptor proteins were expressed at high level in the yeast. Further more, the transformants of P. pastoris were monitored with confocal microscopy, a strong green fluorescence was checked out. The recombinant B2R receptor proteins were mainly located on the plasma membrane proved by immunofluorescence microscopy.