Expression of the choline acetyltransferase gene depends on protein kinase A activity.
Choline acetyltransferase activity is barely detectable in a mutant pheochromocytoma PC12 cell line, A123.7, which is deficient in protein kinase A activity. Northern blot and polymerase chain reaction analyses showed that this mutant cell line has dramatically reduced levels of choline acetyltransferase mRNA, which correlates with the low level of enzyme activity. Transient transfection analysis was used to assess the functionality, in these cells, of an enhancer element and a cholinergic-specific repressor element derived from the human choline acetyltransferase gene. The results show that the enhancer element is inactive in the protein kinase A-deficient cell line. Cotransfection experiments with plasmids expressing the catalytic subunit of protein kinase A support this conclusion. These data indicate that protein kinase A regulates expression of the choline acetyltransferase gene at the transcriptional level by controlling the activity of an enhancer element.
Inoue
H
H
Department of Biochemistry, University of Kentucky, Lexington 40536-0084.
Li
Y P
YP
Wagner
J A
JA
Hersh
L B
LB
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002795:Choline O-Acetyltransferase / Q000235:genetics*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000172:deficiency / Q000502:physiology*; D017931:DNA Primers / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D015971:Gene Expression Regulation, Enzymologic; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism; D016716:PC12 Cells; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats
D017931:DNA Primers; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; D002795:Choline O-Acetyltransferase; D017868:Cyclic AMP-Dependent Protein Kinases