Journal article
Developmental up-regulation and agonist-dependent down-regulation of GABAA receptor subunit mRNAs in chick cortical neurons
Molecular Brain Research, Vol.26(1-2), pp.9-17
1994
Abstract
We have used quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) to analyze the expression of GABAA receptor subunit genes in cultured neurons from the chick embryo cerebral cortex. During maturation of the neurons between day 2 and day 8 in culture, levels of the α1 subunit transcript (per ng total RNA) increased 3.8±0.3 fold, while those for the β2S and β4S subunits increased 2.4±0.4 and 1.8±0.2 fold, respectively. The accumulation of the β4S subunit mRNA was more rapid than those encoding either the α1 or β2S polypeptides. After 4 days in culture the β4S subunit transcript level reached 105±7.7% of that found after 8 days, while the corresponding amounts for the α1 and β2S subunit mRNAs were 50±7.1% and 44±10.7%, respectively. On the other hand, no significant differences were observed in the level of either the γ1 or the γ2S subunit mRNA during development in vitro. Likewise, the ratios of the large/small splice variants (β2 = 0.16±0.02; β4 = 0.57±0.02; γ2 = 0.30±0.06) did not show detectable changes during this period. To study the down-regulation of the mRNAs, a single dose of 100 μM GABA was added to the culture medium. After 7 days of exposure to GABA, the levels of transcripts for the α1, β2, β4, γ1, and γ2 subunits and their splice variants (where present) were all reduced by 47-65% compared to untreated controls. However, GABA treatment for 4 days did not produce a significant change in the level of the α1 subunit mRNA. The subunit specificity observed for developmental up-regulation and the lack of specificity in down-regulation suggests that mRNA down-regulation does not involve suppression of a developmental process. Comparisons with previous work indicate that the GABA-dependent reduction in the levels of subunit transcripts occurs after the loss of GABAA receptor binding sites [Hablitz et al., Brain Res., 501 (1989) 332-338] and subunit polypeptides [Calkin and Barnes, J. Biol. Chem., 269 (1994) 1548-1553]. Thus, for the down-regulation of GABAA receptors, it appears that translational or post-translational mechanisms may take precedence over the controlled synthesis or stability of subunit mRNAs. © 1994.
Details
- Title
- Developmental up-regulation and agonist-dependent down-regulation of GABAA receptor subunit mRNAs in chick cortical neurons
- Authors
- B J Baumgartner (Author) - Baylor College of Medicine, United StatesRobert J Harvey (Author) - Universität Hamburg, GermanyM G Darlison (Author) - Universität Hamburg, GermanyE M Barnes Jr (Author) - Baylor College of Medicine, United States
- Publication details
- Molecular Brain Research, Vol.26(1-2), pp.9-17
- Publisher
- Elsevier BV
- DOI
- 10.1016/0169-328X(94)90068-X
- ISSN
- 0169-328X
- Organisation Unit
- Centre for Bioinnovation; School of Health and Behavioural Sciences - Legacy; School of Health and Sport Sciences - Legacy; University of the Sunshine Coast, Queensland; School of Health
- Language
- English
- Record Identifier
- 99450552702621
- Output Type
- Journal article
Metrics
1 File views/ downloads
406 Record Views
InCites Highlights
These are selected metrics from InCites Benchmarking & Analytics tool, related to this output
- Collaboration types
- Domestic collaboration
- International collaboration
- Web Of Science research areas
- Neurosciences
UN Sustainable Development Goals (SDGs)
This output has contributed to the advancement of the following goals:
Source: InCites