Genetic tracing of the neural pathway for bitter taste in t2r5-WGA transgenic mice.
To visualize the neural pathways originating from bitter taste receptor cells (TRCs), we generated transgenic mice expressing the transneuronal tracer wheat germ agglutinin (WGA) under the control of the mouse T2R5 gene promoter/enhancer (t2r5-WGA mice). WGA mRNA was specifically expressed in bitter TRCs. The WGA protein was detected in bitter TRCs and nerve processes in taste buds, but not in sweet, umami, or sour TRCs. The WGA protein was transferred to a subset of sensory neurons in the geniculate and nodose/petrosal ganglia. These results suggest that bitter TRCs, which are devoid of synaptic structures, are innervated by gustatory neurons and that bitter sensory information is directly transmitted to specific gustatory neurons. The t2r5-WGA mice provide a useful tool for identifying gustatory relay neurons in the peripheral sensory ganglia responsible for aversive sensations.
Ohmoto
Makoto
M
Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Maeda
Naohiro
N
Abe
Keiko
K
Yoshihara
Yoshihiro
Y
Matsumoto
Ichiro
I
D000818:Animals; D051379:Mice; D008822:Mice, Transgenic; D009434:Neural Pathways; D009475:Neurons, Afferent / Q000502:physiology*; D009620:Nodose Ganglion / Q000166:cytology / Q000502:physiology*; D043562:Receptors, G-Protein-Coupled / Q000235:genetics*; D013649:Taste / Q000235:genetics*; D055697:Taste Perception / Q000235:genetics*; D014909:Wheat Germ Agglutinins / Q000235:genetics* / Q000378:metabolism; D000098706:Taste Receptors, Type 2
D043562:Receptors, G-Protein-Coupled; D014909:Wheat Germ Agglutinins; D000098706:Taste Receptors, Type 2