title: Lrmp/Jaw1 is expressed in sweet, bitter, and umami receptor-expressing cells.
abstract: Inositol 1,4,5-triphosphate-mediated calcium (IP3-Ca2+) signal cascade is an essential process in sweet, bitter, and umami taste signal transduction. Although the main components of this cascade have been identified, the candidate regulators of them in taste tissues are still unclear. In an effort to identify genes involved in taste signal transduction, we found that a gene encoding lymphoid-restricted membrane protein (Lrmp/Jaw1) was expressed in mouse taste tissues. Here we report that Lrmp/Jaw1 is specifically expressed in sweet, bitter, and umami taste receptor-expressing cells of mouse circumvallate, foliate, and fungiform papillae. In addition to this specific expression patterns, we found that Lrmp/Jaw1 is associated with type III IP3 receptor (IP3R3) via its coiled-coil domain in the COS7 heterologous expression system. These results raise the possibility that Lrmp/Jaw1 interacts with IP3R3 in taste cells and suggest an important role for Lrmp/Jaw1 in the IP3-Ca2+ signal cascade in sweet, bitter, and umami taste signal transduction.
authors.affiliation: Sensory and Cognitive Food Sciences, National Food Research Institute, 2-1-12 Kannondai, Tsukuba-shi, Ibaraki 305-8642, Japan.
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Shindo
authors.forename: Mi-Ryung
authors.initials: MR
authors.lastname: Kim
authors.forename: Hirohito
authors.initials: H
authors.lastname: Miura
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Yuuki
authors.forename: Tomomasa
authors.initials: T
authors.lastname: Kanda
authors.forename: Akihiro
authors.initials: A
authors.lastname: Hino
authors.forename: Yuko
authors.initials: Y
authors.lastname: Kusakabe
mesh_terms: D000818:Animals; D019556:COS Cells; D020013:Calcium Signaling; D002522:Chlorocebus aethiops; D053496:Inositol 1,4,5-Trisphosphate Receptors / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D015398:Signal Transduction; D013649:Taste / Q000235:genetics / Q000502:physiology*; D013650:Taste Buds / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D053496:Inositol 1,4,5-Trisphosphate Receptors; C101764:Lrmp protein, mouse; D008565:Membrane Proteins