A Novel Regulatory Element of a Nicotinic Acetylcholine Receptor Gene Interacts with a DNA Binding Activity Enriched in Rat Brain (∗)

• Published in: The Journal of biological chemistry Vol. 270; no. 9; pp. 4497 - 4502
• Main Authors: Hu, Minjie, Bigger, Catherine B., Gardner, Paul D.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 03.03.1995; American Society for Biochemistry and Molecular Biology
• Subjects: Animals; Base Sequence; Brain - metabolism; Cell Line; DNA - metabolism; DNA-Binding Proteins - metabolism; Female; Gene Expression Regulation; Molecular Sequence Data; Molecular Weight; Mutagenesis, Site-Directed; Promoter Regions, Genetic; Protein Binding; Rats; Rats, Sprague-Dawley; Receptors, Nicotinic - genetics; Receptors, Nicotinic - metabolism; Regulatory Sequences, Nucleic Acid; Transcription, Genetic
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.270.9.4497

Nicotinic acetylcholine receptors are ligand-gated ion channels that play a critical role in signal transmission in the nervous system. The genes encoding the various subunits that comprise functional acetylcholine receptors are expressed in distinct temporal and spatial patterns. Studies to understand the molecular mechanisms underlying the differential expression of the receptor subunit genes have led to the identification, in this report, of a 19-base pair cis-acting element that is required for transcriptional activation of the rat β4 subunit gene. Screening of computer data bases with the 19-base pair element revealed the sequence to be unique among known transcriptional regulatory elements. Loss of this element resulted in drastically reduced β4 promoter activity in transfected cholinergic SN17 cells. Furthermore, this element specifically interacts with nuclear proteins prepared from both SN17 cells and adult rat brain. UV cross-linking experiments indicated the presence, in SN17 nuclear extracts, of a prominent protein species (approximately 50 kDa) that interacts specifically with the 19-base pair element. These results lead us to hypothesize that interactions between the 50-kDa protein and the novel 19-base pair element are necessary for transcriptional activation of the β4 subunit gene.