Molecular identification of a taste receptor gene for trehalose in drosophila

Science

Volumn 289, Issue 5476, 2000, Pages 116-119

  Ishimoto, Hiroshi ^a   Matsumoto, Akira ^a   Tanimura, Teiichi ^a  

^a KYUSHU UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

TREHALOSE;

ARTICLE; DROSOPHILA MELANOGASTER; GENE; GENE DELETION; GENE MUTATION; GENE OVEREXPRESSION; MOLECULAR BIOLOGY; NONHUMAN; PRIORITY JOURNAL; PROTEIN EXPRESSION; TASTE BUD;

ANIMALS; ANIMALS, GENETICALLY MODIFIED; BLOTTING, SOUTHERN; CLONING, MOLECULAR; DNA, COMPLEMENTARY; DROSOPHILA MELANOGASTER; DROSOPHILA PROTEINS; FEMALE; GENES, INSECT; IN SITU HYBRIDIZATION, FLUORESCENCE; MALE; MOLECULAR SEQUENCE DATA; MUTATION; PROTEIN STRUCTURE, TERTIARY; RECEPTORS, CELL SURFACE; RECEPTORS, G-PROTEIN-COUPLED; TASTE; TREHALOSE;

DROSOPHILA MELANOGASTER; MELANOGASTER;

EID: 0034617002     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.289.5476.116     Document Type: Article

References (32)

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21. All behavioral tests were done at 24° to 25°C. Two-choice preference test was performed as described (12). We used 2 mM of sucrose, colored red, as a control and varying concentrations of trehalose, which was colored blue.
22. Proboscis extension reflex was examined as previously described [K.-I. Kimura, T. Shimozawa, T. Tanimura, J. Exp. Zool. 239, 393 (1986)]. Flies aged 0 to 1 day after eclosion were maintained on fresh medium for 1 day. Flies were starved for 16 hours but were supplied with water. Before the test with sugar solutions, the prothoractic tarsi of a fly was touched with a drop of water and if they extended the proboscis, water was fully fed. This procedure was repeated between stimulations with sugar solutions.
23. Nerve responses were recorded from the labellar chemosensilla by the tip-recording method (10). Numbers of nerve impulses (±SD) originated from the sugar receptor cell 0.2 to 0.4 s after the onset of stimulations were counted. The number of impulses to 10 mM sucrose was 6.1 ± 2.5 (n = 34) and 6.7 ± 2.8, (n = 34) in EP(X)0496 and ΔTre1#1, respectively. The number to 60 mM trehalose was 7.3 ± 2.6 (n = 24) and 1.8 ± 2.3 (n = 26). n, number of recordings from different chemosensilla. Trehalose response difference was statistically significant by t-test (P < 0.001).
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32. We are grateful to K.-I. Kimura for poxn and K. Basler for plasmid. EP lines and other fly strains were provided by the Bloomington stock center and the Berkeley Drosophila Genome Project. The monoclonal antibody 22C10 was obtained from the Developmental Studies Hybridoma Bank at The University of Iowa. We thank T. Hirozane for her initial extensive attempt on this project and T. Hirozane and T. Tamura for their help in sequencing. We also thank Y. Mitsuiki, M. Haruta, M. Yamasaki for their technical assistance and C. Montell for critically reading the early version of our manuscript. Supported by grants from the Ministry of Education, Science, Sports and Culture of Japan and by a Human Frontier Science Program grant to T.T. The Tre1 cDNA sequences have been deposited in DDBJ (accession number AB034204). This paper is dedicated to the memory of the late Dr. Toshihide Kikuchi.