Transient receptor potential channel M5 and phospholipaseC-β2 colocalizing in zebrafish taste receptor cells

In mammals, transient receptor potential (TRP) channel M5 (TRPM5) is coexpressed with phospholipaseC-beta 2 (PLC-beta 2) in the taste receptor cells, and both PLC-beta 2 and TRPM5 are essential elements in the signal transduction of sweet, bitter and umami stimuli. In this study, we identified the zebrafish homologue of TRPMS (zfFRPM5) and examined its expression in the gustatory system by in-situ hybridization. Using a transgeric zebrafish line that expressed green fluorescent protein under the control of the PLC-beta 2 promoter, we showed that zfTRPM5 is expressed in green fluorescent protein-labeled cells of the taste buds. These results demonstrate that zfTRPM5 and PLC-beta 2 colocalize in zebrafish taste receptor cells, suggesting their crucial roles in taste signaling via the fish taste receptors.