Transcription factor AP-2 mediates induction by two different signal-transduction pathways: protein kinase C and cAMP

Cell. 1987 Oct 23;51(2):251-60. doi: 10.1016/0092-8674(87)90152-8.


We have purified and characterized the 50 kd activator protein 2 (AP-2), another enhancer-binding protein interacting with the human metallothionein IIA (hMT-IIA) gene control region. Purified AP-2 activates transcription in vitro from a hybrid promoter containing hMT-IIA upstream sequences. AP-2 also recognizes control elements of the human growth hormone, c-myc, and H-2Kb genes, and the SV40 and bovine papilloma virus enhancers. Multiple synthetic copies of the hMT-IIA high-affinity AP-2 binding site can act as efficient, cell-type-specific enhancer elements; their activity increases after treatment of cells with phorbol ester or cAMP-elevating agents. In contrast, a synthetic enhancer recognized by factor AP-1 is activated only by phorbol ester. AP-2 appears to mediate transcriptional activation in response to two different signal-transduction pathways, one involving the phorbol-ester- and diacylglycerol-activated protein kinase C, the other involving cAMP-dependent protein kinase A.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Binding Sites
  • Cell Physiological Phenomena
  • Cells / classification
  • Cyclic AMP / metabolism*
  • Enhancer Elements, Genetic
  • Genes, Regulator*
  • Genes, Viral
  • Humans
  • Metallothionein / genetics
  • Metallothionein / metabolism
  • Protein Kinase C / metabolism*
  • Transcription Factors / isolation & purification
  • Transcription Factors / metabolism
  • Transcription Factors / pharmacology
  • Transcription Factors / physiology*
  • Transcription, Genetic / drug effects


  • Transcription Factors
  • Metallothionein
  • Cyclic AMP
  • Protein Kinase C