A Binary Genetic Approach to Characterize TRPM5 Cells in Mice

Chem Senses. 2015 Jul;40(6):413-25. doi: 10.1093/chemse/bjv023. Epub 2015 May 4.


Transient receptor potential channel subfamily M member 5 (TRPM5) is an important downstream signaling component in a subset of taste receptor cells making it a potential target for taste modulation. Interestingly, TRPM5 has been detected in extra-oral tissues; however, the function of extra-gustatory TRPM5-expressing cells is less well understood. To facilitate visualization and manipulation of TRPM5-expressing cells in mice, we generated a Cre knock-in TRPM5 allele by homologous recombination. We then used the novel TRPM5-IRES-Cre mouse strain to report TRPM5 expression by activating a τGFP transgene. To confirm faithful coexpression of τGFP and TRPM5 we generated and validated a new anti-TRPM5 antiserum enabling us to analyze acute TRPM5 protein expression. τGFP cells were found in taste bud cells of the vallate, foliate, and fungiform papillae as well as in the palate. We also detected TRPM5 expression in several other tissues such as in the septal organ of Masera. Interestingly, in the olfactory epithelium of adult mice acute TRPM5 expression was detected in only one (short microvillar cells) of two cell populations previously reported to express TRPM5. The TRPM5-IC mouse strain described here represents a novel genetic tool and will facilitate the study and tissue-specific manipulation of TRPM5-expressing cells in vivo.

Keywords: Cre recombinase; IRES; ROSA26; TRPM5; gastrointestinal tract; gene targeting; knock-in; microvillar cells; olfactory epithelium; septal organ of Masera; taste buds; taste papillae; taste receptor cells; vomeronasal organ; τGFP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Animals
  • Antibodies / immunology
  • Female
  • Gastrointestinal Tract / metabolism
  • Gene Knock-In Techniques
  • Genotype
  • Immunohistochemistry
  • In Situ Hybridization, Fluorescence
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Olfactory Mucosa / metabolism
  • Palate / metabolism
  • TRPM Cation Channels / genetics
  • TRPM Cation Channels / immunology
  • TRPM Cation Channels / metabolism*
  • Taste Buds / metabolism
  • Tongue / metabolism


  • Antibodies
  • TRPM Cation Channels
  • Trpm5 protein, mouse