The Timing of α-Gustducin Expression during Cell Renewal in Rat Vallate Taste Buds
The G protein subunita α-gustducin is expressed in a subset of light (Type II) but not in dark (Type I) cells in rat vallate taste buds. The thymidine analogue 5-bromo-2′-deoxyuridine (BrdU) is incorporated into DNA during the S-phase of the cell cycle and can be used to determine the time of origin...
Saved in:
Published in | Chemical senses Vol. 23; no. 6; pp. 735 - 742 |
---|---|
Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Oxford
Oxford University Press
01.12.1998
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | The G protein subunita α-gustducin is expressed in a subset of light (Type II) but not in dark (Type I) cells in rat vallate taste buds. The thymidine analogue 5-bromo-2′-deoxyuridine (BrdU) is incorporated into DNA during the S-phase of the cell cycle and can be used to determine the time of origin of a cell. In this study, 31 rats were injected with BrdU (50 mg/kg i.p.) and perfused at various times, from 2.5 to 10.5 days, following BrdU administration. Vallate papillae were embedded in polyester wax, cut into 4 μm transverse sections, and characterized with antibodies to BrdU and α-gustducin. Sections were processed for indirect immunofluorescence or with an immunoperoxidase procedure. From immunoperoxidase material on 21 rats, counts of α-gustducin- and BrdU-labeled cells were obtained from 300–800 taste bud profiles at each survival time; a total of 4122 taste bud profiles were examined. Cells with nuclei immunoreactive for BrdU occurred within the taste buds at 2.5 days and double-labeled cells were clearly evident at 3.5 days; a small number of double-labeled cells were seen as early as 2.5 days. Double-labeled cells reached a peak at 6.5 days and did not decline significantly by 10.5 days. Cells labeled for BrdU but not α-gustducin peaked at 5.5 days and showed a significant decline by 8.5 days. These latter cells included light cells not expressing α-gustducin and dark cells, which have previously been shown to have a shorter life span than light cells. These data suggest that expression of a-gustducin appears very early in a cell's life span and that these cells are longer lived than many of the cells that do not express this G protein. |
---|---|
Bibliography: | ArticleID:23.6.735 ark:/67375/HXZ-1XBBVLTH-G istex:D2FE16DAFF95C4D27FB05FC136776F81D84A71EE ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 0379-864X 1464-3553 |
DOI: | 10.1093/chemse/23.6.735 |