Fig. 1
From: Single olfactory receptors set odor detection thresholds
Removing olfactory TAARs causes detection deficits to amines. a Diagram of the wild-type mouse TAAR gene cluster (wt) and cluster deletion (ΔT2-9). Olfactory TAARs (white) and non-olfactory Taar1 (shaded) are shown (polygons reflect gene orientation). LoxP site indicated as black triangle. b Schematic of odor delivery for thresholding in head-fixed mice. Flow dilution olfactometer switches between a pressure-balanced dummy (D) carrier vial (via normally open valves, green) and either odor (O) or blank (B) vials (via normally closed valves, red). During stimulus application, a final valve re-directs pressure-balanced, odorized air from exhaust to the animal. Mice lick for water reward in Go/No-Go detection task. c–e Psychometric curves of wild-type (black) and mice lacking all olfactory TAARs (purple) to two amines (isopentylamine and phenylethylamine) and one non-amine (methyl valerate). Plots show mean +/− SE with a shaded 95% confidence interval. Data were fitted with a Hill function. Behavioral sensitivity is defined as the odor concentration at half-maximal behavioral performance (C½) during a head-fixed Go/No-Go conditioned assay. Methyl valerate: wt C½ = 1.7 × 10−12 M (95% CI = 0.9–3.5 × 10−12 M); ΔT2-9 C½ = 1.3 × 10−12 M (95% CI = 0.7–2.2 × 10−12 M). Isopentylamine: wt C½ = 5.9 × 10−10 M (95% CI = 3.0–11.2 × 10−10M); ΔT2-9 C½ = 5.8 × 10−9 M (95% CI = 3.7–9.0 × 10−9 M). Phenylethylamine: wt C½ = 5.0 × 10−12 M (95% CI = 3.2–7.6 × 10−12 M); ΔT2-9 C½ = 9.6 × 10−11 M (95% CI = 6.2–12.1 × 10−11 M)
