ISHIMARU YOSHIRO    Department   Undergraduate School  , School of Agriculture    Position   Professor
Research Period	2008～2009
Research Topic	The in vivo roles of PKD1L3 and PKD2L1 in sour taste detection
Research Type	KAKENHI Research
Consignor	Japan Society for the Promotion of Science
Research Program Type	Grant-in-Aid for Young Scientists (B)
KAKENHI Grant No.	20780089
Responsibility	Representative Researcher
Representative Person	ISHIMARU Yoshiro
Details	We identified the N-terminal extracellular region of human PKD1L3 and the full-length of human PKD2L1. HEK 293T cells expressing human PKD2L1 and chimeric PKD1L3, which consists of the N-terminal extracellular region of human PKD1L3 and the following region of mouse PKD1L3, showed off-response upon stimulation with sour solution such as citric acid. These cells still showed robust response to sour stimuli in the presence of a taste-modifying protein, neoculin, extracted from Curculigo latifolia. These results raise the possibility that neoculin inhibits the region other than the N-terminal extracellular region of human PKD1L3. Alternatively, inhibition event occurs at the level of taste cells or taste neurons, not at the taste receptors.