Transcriptional activation of the rat glucagon gene by the cyclic AMP-responsive element in pancreatic islet cells.
The 5'-flanking region of the rat glucagon gene contains, from nucleotides -291 to -298, a sequence (TGA CGTCA) which mediates cyclic AMP (cAMP) responsiveness in several genes (cAMP-responsive element [CRE]). However, because of nonpermissive bases surrounding the CRE octamer, the glucagon CRE does not confer cAMP responsiveness to an inert heterologous promoter in placental JEG cells that do not express the glucagon gene. This report describes transient transfection experiments with glucagon-reporter fusion genes that show that glucagon gene expression is activated by cAMP-dependent protein kinase A in a glucagon-expressing pancreatic islet cell line. This activation is mediated through the glucagon CRE.
Knepel
W
W
Laboratory of Molecular Endocrinology, Massachusetts General Hospital, Boston.
Chafitz
J
J
Habener
J F
JF
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D017362:Cyclic AMP Response Element-Binding Protein; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005786:Gene Expression Regulation; D005796:Genes; D005934:Glucagon / Q000096:biosynthesis / Q000235:genetics*; D007515:Islets of Langerhans / Q000378:metabolism*; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D010957:Plasmids; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats; D014158:Transcription, Genetic
D017362:Cyclic AMP Response Element-Binding Protein; D004268:DNA-Binding Proteins; D046911:Macromolecular Substances; D005934:Glucagon; D011494:Protein Kinases