Int J Oral Biol.  2016 Mar;41(1):25-32. 10.11620/IJOB.2016.41.1.025.

Differential Expression of Taste Receptors in Tongue Papillae of DBA Mouse

• Choi HJ
• Cho YK
• Chung KM
• Kim KN

• KMID: 2162143
• DOI: http://doi.org/10.11620/IJOB.2016.41.1.025

Abstract

The tongue has 4 kinds of papillae, which are filiform, fungiform (FU), foliate (FO) and circumvallate papilla (CV). Tongue papillae except filiform papilla include taste buds. The papillae differ in taste sensitivities, likely due to differential expression of taste receptors. In this study, we evaluated differences in the expression levels of taste receptors in FU, FO and CV. Male DBA2 mice, 42-60 days old, were used in the study. Messenger RNAs were extracted from the murine epithelial tissues including FU, FO and CV. Cloned DNAs were synthesized by reverse transcription. Quantitative PCRs (qPCRs) were performed to determine mRNA expression levels of taste receptors.
Results
of qPCR revealed that the relative expression levels and patterns were different among FU, FO and CV. All three type 1 taste receptors were expressed FU, FO and CV at varying relative expression levels. All 35 kinds of type 2 taste receptors showed higher expression in FO and CV than in FU. Tas2r108 and Tas2r137 showed the two highest expression levels in all tested papillae. The differential expression levels and patterns of taste receptors among the three papillae could contribute to the different physiological sensitivities by tongue areas. Additional studies such as in situ hybridization or taste receptor cell activity recording is necessary to elucidate the functional relationship between expression levels of taste receptors and taste sensitivity.

Keyword

taste receptors; fungiform papilla; foliate papilla; circumvallate papilla; qPCR

MeSH Terms

Animals
Clone Cells
DNA
Humans
In Situ Hybridization
Male
Mice
Mice, Inbred DBA*
Polymerase Chain Reaction
Reverse Transcription
RNA, Messenger
Taste Buds
Tongue*
DNA
RNA, Messenger