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PubMed · 10976971

GLAST: gene expression regulation by phorbol esters.

M Espinoza-Rojo·E López-Bayghen·A Ortega
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Abstract

The gene expression regulation of the Na+-dependent high affinity glutamate/aspartate transporter GLAST expressed in cultured Bergmann glia cells from chick cerebellum was studied. A 679 bp fragment of the chick GLAST cDNA was cloned and sequenced. Specific PCR primers were used to quantify chick GLAST mRNA levels. Treatment of the cells with the Ca2+/diacylglycerol dependent protein kinase C (PKC) activator, phorbol 12-tetradecanoyl-13-acetate (TPA) produced a decrease in transporter mRNA levels, without an effect in its mRNA half life, suggesting a transcriptional down regulation. Activation of the cAMP pathway results in a transient decrease in GLAST mRNA levels, in contrast with the TPA effect. These findings suggest that GLAST expression is under control of distinct signaling pathways.

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ATP-Binding Cassette TransportersAmino Acid SequenceAmino Acid Transport System X-AGAnimalsBase SequenceCerebellumChick EmbryoCyclic AMP-Dependent Protein KinasesGene ExpressionMolecular Sequence DataProtein Kinase CRNA, MessengerTetradecanoylphorbol AcetateJournal ArticleResearch Support, Non-U.S. Gov't

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M Espinoza-Rojo, E López-Bayghen, A Ortega. 2000-08-21. GLAST: gene expression regulation by phorbol esters.. https://doi.org/10.1097/00001756-200008210-00043

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