Figure 2.

Orthologues of GPR35 elevate [Ca²⁺]_i via a Gα_q/Gα₁₃ chimera but not a Gα_q/Gα₁₂ chimera. (A) HEK293T cells were transfected with either human GPR35 or rat GPR35 and either full length Gα_q or a Gα_q/Gα₁₃ chimera. Single cell Ca²⁺ imaging studies were performed and effects of zaprinast (zap) were recorded in each case. In cells that did not respond to zaprinast (black, blue), ATP was added subsequently to activate endogenously expressed P2Y purinoceptors. (B) Similar studies were performed on cells transfected to express human GPR35 or rat GPR35 and a Gα_q/Gα₁₂ chimera. As in (A), cells transfected to express the Gα_q/Gα₁₂ chimera, although producing little response to zaprinast, were subsequently challenged with ATP to confirm that [Ca²⁺]_i could be elevated in these cells. At least 20 cells were examined for each condition and data represent means ± SEM.