Physiological and Behavioral Responses to Optogenetic Stimulation of PKD2L1+ Type III Taste Cells

eNeuro. 2019 May 15;6(2):ENEURO.0107-19.2019. doi: 10.1523/ENEURO.0107-19.2019. Print 2019 Mar/Apr.


Type III taste cells in mammalian taste buds are implicated in the detection and communication of sour and some salty stimuli, as well as carbonation and water. With this variety of proposed roles, it is unclear what information activated type III cells are communicating to the CNS. To better elucidate the role of type III cells in the taste bud, we use a type III cell-specific protein (polycystic kidney disease 2-like 1) to drive Cre-dependent expression of light-sensitive channelrhodopsin (Ai32) in mouse type III taste cells. Activation of these cells with light produces a taste nerve response in both the chorda tympani and glossopharyngeal nerves, and elicits a slight but significant aversion in two-bottle preference tests in both male and female mice. Unlike previous reports (Zocchi et al., 2017), our mice did not react to blue light stimulation with sustained drinking responses. These data suggest that type III cells are capable of communicating the presence of aversive stimuli in the oral cavity, which is in line with their responsiveness to sour and high concentrations of salt stimuli.

Keywords: optogenetics; taste; type III taste cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Behavior, Animal / physiology
  • Calcium Channels*
  • Channelrhodopsins / metabolism*
  • Choice Behavior / physiology
  • Chorda Tympani Nerve / physiology
  • Female
  • Glossopharyngeal Nerve / physiology
  • Light
  • Male
  • Mice
  • Optogenetics*
  • Receptors, Cell Surface*
  • Taste / physiology*
  • Taste Buds / physiology*
  • Taste Perception / physiology*


  • Calcium Channels
  • Channelrhodopsins
  • Pkd2l1 protein, mouse
  • Receptors, Cell Surface