title: Transient receptor potential family members PKD1L3 and PKD2L1 form a candidate sour taste receptor.
abstract: Animals use their gustatory systems to evaluate the nutritious value, toxicity, sodium content, and acidity of food. Although characterization of molecular identities that receive taste chemicals is essential, molecular receptors underlying sour taste sensation remain unclear. Here, we show that two transient receptor potential (TRP) channel members, PKD1L3 and PKD2L1, are coexpressed in a subset of taste receptor cells in specific taste areas. Cells expressing these molecules are distinct from taste cells having receptors for bitter, sweet, or umami tastants. The PKD2L1 proteins are accumulated at the taste pore region, where taste chemicals are detected. PKD1L3 and PKD2L1 proteins can interact with each other, and coexpression of the PKD1L3 and PKD2L1 is necessary for their functional cell surface expression. Finally, PKD1L3 and PKD2L1 are activated by various acids when coexpressed in heterologous cells but not by other classes of tastants. These results suggest that PKD1L3 and PKD2L1 heteromers may function as sour taste receptors.
authors.affiliation: Department of Molecular Genetics and Microbiology, Duke University Medical Center, Research Drive, Durham, NC 27710, USA.
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Ishimaru
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Inada
authors.forename: Momoka
authors.initials: M
authors.lastname: Kubota
authors.forename: Hanyi
authors.initials: H
authors.lastname: Zhuang
authors.forename: Makoto
authors.initials: M
authors.lastname: Tominaga
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Matsunami
mesh_terms: D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels; D002460:Cell Line; D006801:Humans; D017403:In Situ Hybridization; D008297:Male; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D018408:Patch-Clamp Techniques; D010750:Phosphoproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D050053:TRPM Cation Channels / Q000235:genetics / Q000378:metabolism; D050396:TRPP Cation Channels / Q000737:chemistry / Q000378:metabolism*; D013649:Taste / Q000502:physiology*; D013650:Taste Buds / Q000166:cytology / Q000378:metabolism*
chemical_list: D015220:Calcium Channels; D008562:Membrane Glycoproteins; C512453:PKD1L3 protein, mouse; D010750:Phosphoproteins; C486487:Pkd2l1 protein, mouse; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins; D050053:TRPM Cation Channels; D050396:TRPP Cation Channels; C498617:Trpm5 protein, mouse; D002118:Calcium