Fig. 4.

CB₁ and T1r3 are coexpressed in taste bud cells. (A) Expression of gustducin (40, 45, and 50 cycles), CB₁ (40, 45, and 50 cycles), CB₂ (40, 45, and 50 cycles), and β-actin (25, 30, and 35 cycles) mRNAs in fungiform taste buds (FP), circumvallate taste buds (CV), and tongue epithelium devoid of TCs (ET). M, 100-bp marker. (B) Coexpression patterns of CB₁ with: T1r3 (Left), GAD67 (Middle), and GLAST (Right) in FP and CV of T1r3-GFP or WT mice. Immunostaining for CB₁ is shown in red. T1r3-GFP expression and immunostaining for GAD and GLAST are shown in green. (Scale bar, 10 μm.) Negative control and immunostaining in CB₁^−/− mice are shown in Fig. S7.