Cloning of the Ah-receptor cDNA reveals a distinctive ligand-activated transcription factor.
A cDNA encoding the murine Ah receptor (Ahb-1 allele for aromatic hydrocarbon responsiveness) has been isolated and characterized. Analysis of the deduced protein sequence revealed a region with similarity to the basic region/helix-loop-helix (BR/HLH) motif found in many transcription factors that undergo dimerization for function. In addition to the BR/HLH domain, the N-terminal domain of the Ah receptor has extensive sequence similarity to the human ARNT (aryl hydrocarbon receptor nuclear translocator) protein and two regulatory proteins of Drosophila, Sim and Per. Photoaffinity labeling and peptide mapping studies indicate that the Ah receptor binds agonist at a domain that lies within this conserved N-terminal domain. The Ah receptor appears to be a ligand-activated transcription factor with a helix-loop-helix motif similar to those found in a variety of DNA-binding proteins, including Myc and MyoD.
Burbach
K M
KM
Department of Pharmacology, Northwestern University Medical School, Chicago, IL 60611.
Poland
A
A
Bradfield
C A
CA
D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D016384:Consensus Sequence; D004247:DNA / Q000235:genetics; D015870:Gene Expression; D066298:In Vitro Techniques; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D010449:Peptide Mapping; D012333:RNA, Messenger / Q000235:genetics; D018336:Receptors, Aryl Hydrocarbon; D011955:Receptors, Drug / Q000235:genetics*; D015183:Restriction Mapping; D016415:Sequence Alignment; D014157:Transcription Factors / Q000235:genetics*; D014407:Tumor Cells, Cultured
D010446:Peptide Fragments; D012333:RNA, Messenger; D018336:Receptors, Aryl Hydrocarbon; D011955:Receptors, Drug; D014157:Transcription Factors; D004247:DNA