In rat astroglial cells, four G(oα) transcripts were found: G(o2α) mRNA (5.7 kb) and three G(o1α) mRNAs (4.0, 3.0 and 2.3 kb). However, G(o2α) but little G(oα1) proteins were present in membrane-enriched fractions. Culturing astroglial cells with forskolin (10 μM) or isoproterenol (10 μM) a β-adrenergic agonist increased transiently in a time-dependent manner the levels of G(oα) proteins. The degradation rate of G(oα) proteins was slightly decreased by the cAMP treatment. In parallel, forskolin (10 μM) treatment increased transiently the amounts of both G(o1α) and G(o2α) mRNAs. The relative transcription rate of G(oα) gene was increased by 1.7-fold in forskolin-treated cells whereas the half-lives of G(o1α) and G(o2α) mRNAs were not significantly changed. These results suggest that cAMP regulates the transcription rate of G(oα) gene and this is compatible with the existence of a cAMP responsive element in the promoter of the G(oα) gene. Copyright (C) 1999 Elsevier Science Ireland Ltd.
- Brain astrocytes (newborn rat)
- Cyclic adenosine monophosphate
- Go alpha mRNAs
- Go alpha proteins
ASJC Scopus subject areas
- Molecular Biology