BRET values for cells expressing GIPR and GLP1R suggest heteromeric and homomeric associations.

<p>Plots of BRET<sup>2</sup> ratio versus the ratio of GFP/Luc from cells co-expressing RLuc- and GFP-tagged combinations of GIPR, GLP1R and HCN2 channels. (<b>A</b>) Curves from GIPR+GLP1R (Bmax = 0.073±0.003) compared to GIPR+HCN2 negative control (Bmax = 0.028±0.004). (<b>B</b>) Curves from GLP1R+GLP1R (Bmax = 0.15±0.03), compared to GLP1R+HCN2 negative control (Bmax = 0.029±0.006). (<b>C</b>) Curves from GIPR+GIPR (Bmax = 0.13±0.02), compared to GIPR+HCN2 negative control (Bmax = 0.0<i>28±0.004</i>). Data were collected from at least separate 5 transfections and fit with a non-linear regression equation assuming a single binding site; they were statistically analyzed using a two-taile<i>d u</i>npaired t test and for all conditions, Bmax was significantly greater than negative controls, p<0.001.</p>