Identification of a cAMP-responsive region in thyroglobulin gene promoter.
The DNA sequences involved in transcription control by a cAMP-dependent mechanism have been localized in the thyroglobulin gene promoter region by a functional assay. The proximal 5'-flanking sequences from the bovine thyroglobulin gene were linked to the bacterial chloramphenicol acetyl-transferase gene. Transient expression of this reporter gene was studied in dog thyrocytes in primary culture in the presence, or absence, of cAMP stimulation. Deletion analysis showed that the cAMP-responsive region is contained within the first 250 base-pairs of the promoter, and suggests that it could correspond to a sequence conserved between species. These DNA sequences do not bear significant homology with cAMP-responsive elements (CRE) described previously. By contrast, some similarities were found with the fat-specific element (FSE2) of genes under cAMP control in adipocytes and with DNA elements mediating cAMP-dependent regulation of expression of two different genes in the lower eukaryote Dictyostelium discoideum. This suggests that control of Tg gene transcription by cAMP could involve a mechanism different from the one mediated by a classical CRE.
Christophe
D
D
I.R.I.B.H.N., Université Libre de Bruxelles, Campus Erasme, Belgium.
Gérard
C
C
Juvenal
G
G
Bacolla
A
A
Teugels
E
E
Ledent
C
C
Christophe-Hobertus
C
C
Dumont
J E
JE
Vassart
G
G
D000273:Adipose Tissue / Q000166:cytology; D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D015500:Chloramphenicol O-Acetyltransferase / Q000032:analysis / Q000235:genetics; D003001:Cloning, Molecular; D000242:Cyclic AMP / Q000235:genetics*; D004023:Dictyostelium / Q000235:genetics; D004285:Dogs; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D009710:Nucleotide Mapping; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012689:Sequence Homology, Nucleic Acid; D013954:Thyroglobulin / Q000235:genetics*; D013972:Thyrotropin / Q000502:physiology; D014158:Transcription, Genetic; D014162:Transfection
D013972:Thyrotropin; D013954:Thyroglobulin; D000242:Cyclic AMP; D015500:Chloramphenicol O-Acetyltransferase