TRPM5-null mice showed no licking response to a sweet tastant, a diminished preference ratio for sweet and umami tastants, and a reduced response to bitter taste (Damak et al., 2006). GPR40 and GPR120 were reported to be coexpressed with the TRPM5 (Cartoni et al., 2007). These findings suggest that TRPM5 but not gustducin is one of the signaling components that play a role in fat recognition on the tongue. Signaling pathways involved in fat recognition on the tongue are beginning …