Figure 5. Point mutations of FFAR1/GPR40 differentially affect Ca²⁺ influx activities of fasiglifam and γ-LA.

(A) Relative cell surface expression levels of FLAG-tagged FFAR1 wild-type and mutant receptors in transfected HEK293T cells were determined using flow cytometric analysis (FACS). (B - J) Effects of FFAR1 point mutations on the Ca²⁺ influx activities of FFAR1 agonists. HEK293T cells were transiently transfected with mock vector (B), wild-type (C), S8A (D), Y91A (E), H137A (F), R183A (G), L186F (H), N244A (I), and R258A (J) constructs. Data are representative of three independent experiments. Error bars indicate s.e.m. (n = 3); γ-LA, γ-linolenic acid.