FIG 1.

Dually tagged GIPR reporter constructs. (A) Schematic of GIPR reporters HA-GIPR-GFP and BTX-GIPR-GFP. An HA epitope in the former and a bungarotoxin binding site in the latter are inserted at the amino terminus of GIPR. (B) cAMP production in HEK293 cells stimulated with 100 nM GIP ectopically expressing GIPR (untagged), HA-GIPR-GFP, or BTX-GIPR-GFP. The bar labeled Control shows data from mock-transfected HEK293 cells (no GIPR expression). (C) cAMP production in HEK293 cells expressing HA-GIPR-GFP stimulated with GIP, with or without anti-HA in the incubation medium. (D) cAMP production in HEK293 cells expressing BTX-GIPR-GFP stimulated with GIP, with or without bungarotoxin in the medium. A total of 100 nM GIP was used for the stimulations. Each bar represents the average ± standard error of the mean of data from 3 independent experiments.