TY - JOUR
T1 - Identification of an element required for acetylcholine receptor- inducing activity (ARIA)-induced expression of the acetylcholine receptor ε subunit gene
AU - Si, Jutong
AU - Miller, Daniel S.
AU - Mei, Lin
PY - 1997/4/18
Y1 - 1997/4/18
N2 - Acetylcholine Receptor (AChR)-inducing activity (ARIA) is believed to be the trophic factor utilized by motoneurons to stimulate AChR synthesis in the subsynaptic area. Among the four AChR subunit genes, the ε subunit gene is strictly expressed in nuclei localized to the synaptic region of the muscle. To understand mechanisms of the regulation of synapse-specific transcription, we studied the promoter activity of the 5'-flanking region of the AChR ε subunit gene in response to ARIA. Transgenes containing the wild type or mutant 5'-flanking regions upstream of a luciferase gene were transfected in C2C12 muscle cells. The promoter activity of these transgenes was determined by assaying activity of expressed luciferase. Analyzing a combination of 5' deletion and site-directed mutants, we identified a 10-nucleotide element (position -55/-46), which was crucial for ARIA-induced expression from the ε subunit promoter. This element was named ARE for ARIA-responsive element. Mutation of ARE greatly diminished ARIA-induced transgene expression and deletion of ARE abolished completely the ARIA response. Electrophoretic mobility shift analyses revealed a DNA binding activity in muscle nuclear extract that interacted with ARE. Such interaction was enhanced by ARIA stimulation of muscle cells and appeared to be dependent on nuclear protein phosphorylation.
AB - Acetylcholine Receptor (AChR)-inducing activity (ARIA) is believed to be the trophic factor utilized by motoneurons to stimulate AChR synthesis in the subsynaptic area. Among the four AChR subunit genes, the ε subunit gene is strictly expressed in nuclei localized to the synaptic region of the muscle. To understand mechanisms of the regulation of synapse-specific transcription, we studied the promoter activity of the 5'-flanking region of the AChR ε subunit gene in response to ARIA. Transgenes containing the wild type or mutant 5'-flanking regions upstream of a luciferase gene were transfected in C2C12 muscle cells. The promoter activity of these transgenes was determined by assaying activity of expressed luciferase. Analyzing a combination of 5' deletion and site-directed mutants, we identified a 10-nucleotide element (position -55/-46), which was crucial for ARIA-induced expression from the ε subunit promoter. This element was named ARE for ARIA-responsive element. Mutation of ARE greatly diminished ARIA-induced transgene expression and deletion of ARE abolished completely the ARIA response. Electrophoretic mobility shift analyses revealed a DNA binding activity in muscle nuclear extract that interacted with ARE. Such interaction was enhanced by ARIA stimulation of muscle cells and appeared to be dependent on nuclear protein phosphorylation.
UR - http://www.scopus.com/inward/record.url?scp=0030935377&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0030935377&partnerID=8YFLogxK
U2 - 10.1074/jbc.272.16.10367
DO - 10.1074/jbc.272.16.10367
M3 - Article
C2 - 9099674
AN - SCOPUS:0030935377
SN - 0021-9258
VL - 272
SP - 10367
EP - 10371
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 16
ER -