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Updated: Aug 14, 2026

Methods for the Discovery of Novel Compounds Modulating a Gamma-Aminobutyric Acid Receptor Type A Neurotransmission
07:16

Methods for the Discovery of Novel Compounds Modulating a Gamma-Aminobutyric Acid Receptor Type A Neurotransmission

Published on: August 16, 2018

The alpha1 subunit of GABAA receptor is repressed by c-myc and is pro-apoptotic

Uri A Vaknin1, Stephen R Hann

  • 1Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-2175, USA.

Journal of Cellular Biochemistry
|November 19, 2005
PubMed

Insights

The c-myc oncoprotein represses gamma-aminobutyric acid receptor alpha1 (GABAAR-alpha1) expression. Upregulation of GABAAR-alpha1 induces apoptosis, revealing a novel mechanism linked to Myc proteins in neurological processes.

Area of Science:

  • Molecular Biology
  • Neuroscience
  • Oncology

Background:

  • The c-myc oncoprotein regulates cellular proliferation and apoptosis by modulating target genes.
  • Identifying direct mediators of c-myc's functions in proliferation and apoptosis remains crucial.
  • Gamma-aminobutyric acid receptors (GABAARs) are key inhibitory neurotransmitter receptors in the central nervous system, involved in various developmental processes.

Purpose of the Study:

  • To identify novel target genes directly regulated by c-myc.
  • To investigate the role of GABAAR-alpha1 as a potential mediator of c-myc's functions.
  • To explore the implications of the c-myc/GABAAR-alpha1 interaction in neurological processes.

Main Methods:

  • Gene expression screening to identify c-myc repressed genes.
  • Quantitative analysis of GABAAR-alpha1 expression in relation to c-myc levels.
  • Apoptosis assays involving overexpression of GABAAR subunits and coexpression with anti-apoptotic proteins (Bcl-2, Bcl-XL).

Main Results:

  • GABAAR-alpha1 was identified as a novel gene directly repressed by c-myc.
  • GABAAR-alpha1 expression is elevated in c-myc null cells and inversely correlates with c-myc protein during neuronal differentiation.
  • Overexpression of GABAAR-alpha1 specifically induces apoptosis, which can be blocked by Bcl-2 or Bcl-XL.

Conclusions:

  • c-myc directly represses GABAAR-alpha1 expression, establishing a novel regulatory pathway.
  • Derepression of GABAAR-alpha1 upon c-myc downregulation triggers a unique apoptotic mechanism.
  • This interaction suggests a direct role for Myc proteins in neurological functions and potentially neurodegenerative disorders.

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