Villin is a possible marker of receptor cells in frog taste organs.

We investigated lingual taste organs of four frog species mainly by means of fluorescence immunohistochemistry for villin, calbindin, and serotonin. Cells immunoreactive for villin appeared in the taste organs of all the species used. These villin-immunostained cells were basoapically elongated in shape and extended up to the apical surface. They were also immunoreactive for calbindin. On the other hand, serotonin-immunoreactive cells, identified as Merkel-like basal cells, were immunonegative for villin. Considering the present results combined with those of studies by other research groups, the villin-immunostained cells were postulated to function as taste receptors.