IP(3) receptor type 3 and PLCbeta2 are co-expressed with taste receptors T1R and T2R in rat taste bud cells.
The Ca(2+) signaling cascade has been reported to be activated by many tastants in vertebrate taste systems. Recently we have shown that G(i2) and phospholipase Cbeta2 (PLCbeta2) are co-expressed in a subset of taste bud cells and are possibly involved in Ca(2+) triggering of taste signaling in rats. We report here that, as a component downstream of PLCbeta2, the type 3 isoform of the inositol 1,4,5-trisphosphate (IP(3)) receptor (IP(3)R3) is specifically expressed in the same cells as PLCbeta2 in rat taste buds. We also show that cells expressing rT2R9, a probable cycloheximide receptor, are included among PLCbeta2- and IP(3)R3-positive cells, as in the case of rT1R2, a different type of taste receptor. Our findings indicate that PLCbeta2 and IP(3)R3 co-localize together with G(i2) as downstream components of two different types of taste receptors, T1R and T2R, in taste bud cells.
Miyoshi
M A
MA
Bio-oriented Technology Research Advancement Institution, 1-40-2 Nisshin-cho, Oomiya, Saitama 331-0044, Japan. amiyoshi@mail.ecc.u-tokyo.ac.jp
Abe
K
K
Emori
Y
Y
D000818:Animals; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000096:biosynthesis* / Q000737:chemistry; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007527:Isoenzymes / Q000096:biosynthesis*; D008856:Microscopy, Fluorescence; D054799:Phospholipase C beta; D020033:Protein Isoforms; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D051381:Rats; D011956:Receptors, Cell Surface / Q000096:biosynthesis*; D018160:Receptors, Cytoplasmic and Nuclear / Q000096:biosynthesis* / Q000737:chemistry; D043562:Receptors, G-Protein-Coupled; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012684:Sensory Thresholds; D015398:Signal Transduction; D013649:Taste; D013650:Taste Buds / Q000378:metabolism*; D010738:Type C Phospholipases / Q000096:biosynthesis*; D000098706:Taste Receptors, Type 2
D015220:Calcium Channels; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007527:Isoenzymes; D020033:Protein Isoforms; D011500:Protein Synthesis Inhibitors; D011956:Receptors, Cell Surface; D018160:Receptors, Cytoplasmic and Nuclear; D043562:Receptors, G-Protein-Coupled; C431926:taste receptors, type 1; D000098706:Taste Receptors, Type 2; D003513:Cycloheximide; D010738:Type C Phospholipases; D054799:Phospholipase C beta; D002118:Calcium