Figure 8.

Replacement of Gα_q G.H5.23 Tyr by Leu allows engagement of Gα_q by agonist-occupied hGPR35. A) The ability of varying concentrations of either lodoxamide (i) or bufrolin (ii) to enhance BRET at hGPR35-SPASM sensors containing the C-terminal 27 aa of Gα_q (filled diamonds), G.H5.23Leu Gα_q (shaded diamonds), or Gα₁₃ (triangles) was assessed. B) The ability of varying concentrations of either zaprinast (i) or lodoxamide (ii) to promote shedding of an AP-tagged form of TGF-α was assessed following cotransfection of hGPR35 and AP-TGF-α with either full-length Gα_q (solid diamonds), G.H5.23 Leu Gα_q (shaded diamonds), or chimeric Gα_q/Gα₁₃ containing the C-terminal hexapeptide of Gα₁₃ (squares) into HEK293 cells that had been genome-edited to lack expression of a combination of Gα_q, Gα₁₁, Gα₁₂, and Gα₁₃. Basal levels of AP-TGF-α release were subtracted. Data represent means ± sd in triplicates from each group of a single experiment that is representative of 3 performed.