title: Cyclic AMP decreases the expression of a neuronal marker (GAD67) and increases the expression of an astroglial marker (GFAP) in C6 cells.
abstract: C6 cells express proteins and mRNAs that are characteristic of both glia and neurons. Agents that increase intracellular levels of cyclic AMP (cAMP) decrease the enzymatic activity of glutamate decarboxylase (GAD), a neuronal marker, and the mRNA levels for one of the two GAD isoenzymes, GAD67. This reduction is accompanied by increased levels of glial fibrillary acidic protein (GFAP) mRNA, an astrocyte marker. Transient transfection assays, in which a 2-kb upstream regulatory region of the human GFAP gene was linked to a reporter gene, indicate that at least some of the cAMP-mediated increase of GFAP mRNA levels is due to increased transcription. Increases in intracellular cAMP appear to induce differentiation of C6 cells toward a more mature astrocyte phenotype.
authors.affiliation: Department of Biology, University of California, Los Angeles 90024-1606.
authors.forename: J
authors.initials: J
authors.lastname: Segovia
authors.forename: G M
authors.initials: GM
authors.lastname: Lawless
authors.forename: N J
authors.initials: NJ
authors.lastname: Tillakaratne
authors.forename: M
authors.initials: M
authors.lastname: Brenner
authors.forename: A J
authors.initials: AJ
authors.lastname: Tobin
mesh_terms: D000199:Actins / Q000096:biosynthesis; D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D001483:Base Sequence; D015415:Biomarkers / Q000032:analysis; D001921:Brain / Q000378:metabolism; D002460:Cell Line; D005576:Colforsin / Q000494:pharmacology*; D000242:Cyclic AMP / Q000502:physiology*; D017931:DNA Primers; D015870:Gene Expression / Q000187:drug effects; D005904:Glial Fibrillary Acidic Protein / Q000096:biosynthesis*; D005910:Glioma; D005968:Glutamate Decarboxylase / Q000096:biosynthesis*; D007700:Kinetics; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism*; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000096:biosynthesis; D012334:RNA, Neoplasm / Q000096:biosynthesis; D051381:Rats; D014158:Transcription, Genetic / Q000187:drug effects / Q000502:physiology; D014407:Tumor Cells, Cultured
chemical_list: D000199:Actins; D015415:Biomarkers; D017931:DNA Primers; D005904:Glial Fibrillary Acidic Protein; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D005576:Colforsin; D000242:Cyclic AMP; D005968:Glutamate Decarboxylase