The depolarization response element in acetylcholine receptor genes is a dual-function E box.
All acetylcholine receptor subunit genes contain E boxes and are blocked by membrane depolarization. We have used transfected C2C12 myogenic cells to investigate the response, to electrical stimulation and KCl, of wildtype and mutant regulatory regions of the chick acetylcholine receptor alpha, gamma and delta subunit, and the mouse MLC genes. Point mutations revealed that E boxes function as activating elements targeted by the depolarization signal. These experiments suggest, and insertion of a depolarization response element into an unrelated promoter confirms, that plasma membrane depolarization switches the depolarization response element from an activating to a repressive mode.
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C T
CT
Department of Biochemistry and Cell Biology, State University of New York at Stony Brook 11794, USA.
Huang
C F
CF
Schmidt
J
J
D000200:Action Potentials; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002645:Chickens; D004558:Electric Stimulation; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation; D051379:Mice; D008969:Molecular Sequence Data; D009132:Muscles / Q000166:cytology; D016254:Mutagenesis, Insertional; D016297:Mutagenesis, Site-Directed; D009218:Myosins / Q000096:biosynthesis / Q000235:genetics; D017354:Point Mutation; D011189:Potassium Chloride / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D011950:Receptors, Cholinergic / Q000096:biosynthesis / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012045:Regulatory Sequences, Nucleic Acid; D014162:Transfection
D011950:Receptors, Cholinergic; D011993:Recombinant Fusion Proteins; D011189:Potassium Chloride; D009218:Myosins