Logo image
Back
Developmental up-regulation and agonist-dependent down-regulation of GABAA receptor subunit mRNAs in chick cortical neurons
Journal article   Peer reviewed

Developmental up-regulation and agonist-dependent down-regulation of GABAA receptor subunit mRNAs in chick cortical neurons

B J Baumgartner, Robert J Harvey, M G Darlison and E M Barnes Jr
Molecular Brain Research, Vol.26(1-2), pp.9-17
1994
DOI: https://doi.org/10.1016/0169-328X(94)90068-X
url
https://doi.org/10.1016/0169-328X(94)90068-XView
Published Version

Abstract

GABAA receptor cerebral cortex development downregulation mRNA
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

Metrics

1 File views/ downloads
423 Record Views
38 Times Cited - Web of Science

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:

#3 Good Health and Well-Being

Source: InCites

Logo image