TY - JOUR
T1 - Purified transcription factor AP-1 interacts with TPA-inducible enhancer elements
AU - Lee, Wes
AU - Mitchell, Pamela
AU - Tjian, Robert
N1 - Funding Information:
We thank William Dynan for critical advice and encouragement during the initial phases of this work, and acknowledge his early identification of a DNA-binding activity at the AP-1 site in the SV40 enhancer using fractionated HeLa cell extracts (Dynan and Tjian, 1983b). We thank Michael Karin for stimulating discussions and for supplying various hMT IIA constructs. Peter Herrlich kindly provided us with wild-type and mutant collagenase templates and made unpublished results available to us. We are indebted to the many members of the Tjian lab for critical experimental advice during this work and to Bobbi Johnson for consistent HeLa cell maintenance. Critical reading and discussions with J. Kadonaga, M. Biggin, M. Jantzen, D. Bohmann, K. Perkins, and N. Mermod contributed significantly to the manuscript. This work was funded by a research grant from the National Cancer Institute to R. T., and f? Mitchell is a Damon Runyon Fellowship recipient.
PY - 1987/6/19
Y1 - 1987/6/19
N2 - The enhancer-binding protein AP-1 has been purified to >95% homogeneity from HeLa cells by sequence-specific DNA affinity chromatography and identified as a 47 kd polypeptide. Purified AP-1 activates transcription in vitro of the wild-type human metallothionein IIA (hMT IIA) gene but not mutant hMT IIA promoters lacking AP-1 recognition sites. DNAase I protection analysis indicates that genetically defined enhancer elements in hMT IIA, SV40, and the human collagenase gene contain high-affinity AP-1-binding sites, each with a conserved recognition motif, TGACTCA. These three genes are transcriptionally induced by treatment of cells with the tumor promoter TPA. Here we demonstrate that multiple synthetic copies of the consensus AP-1-binding site can act as TPA-inducible enhancers in various plasmid constructs after transfection into HeLa cells. These findings suggest that AP-1 is a transcription factor that functions by interacting with a specific enhancer element, and that its activities may be modulated by treatment of cells with TPA, known to stimulate protein kinase C.
AB - The enhancer-binding protein AP-1 has been purified to >95% homogeneity from HeLa cells by sequence-specific DNA affinity chromatography and identified as a 47 kd polypeptide. Purified AP-1 activates transcription in vitro of the wild-type human metallothionein IIA (hMT IIA) gene but not mutant hMT IIA promoters lacking AP-1 recognition sites. DNAase I protection analysis indicates that genetically defined enhancer elements in hMT IIA, SV40, and the human collagenase gene contain high-affinity AP-1-binding sites, each with a conserved recognition motif, TGACTCA. These three genes are transcriptionally induced by treatment of cells with the tumor promoter TPA. Here we demonstrate that multiple synthetic copies of the consensus AP-1-binding site can act as TPA-inducible enhancers in various plasmid constructs after transfection into HeLa cells. These findings suggest that AP-1 is a transcription factor that functions by interacting with a specific enhancer element, and that its activities may be modulated by treatment of cells with TPA, known to stimulate protein kinase C.
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U2 - 10.1016/0092-8674(87)90612-X
DO - 10.1016/0092-8674(87)90612-X
M3 - Article
C2 - 3034433
AN - SCOPUS:0023611441
VL - 49
SP - 741
EP - 752
JO - Cell
JF - Cell
SN - 0092-8674
IS - 6
ER -