Cloning and expression of AP-2, a cell-type-specific transcription factor that activates inducible enhancer elements.
Human AP-2 is a sequence-specific DNA-binding protein that interacts with inducible viral and cellular enhancer elements to stimulate transcription of selected genes. Here, we report the isolation and characterization of a human cDNA clone containing the entire protein-coding region of AP-2. The deduced primary amino acid sequence of AP-2 does not contain a domain resembling any previously identified DNA binding motif. However, an interesting feature of the AP-2 protein is a clustered arrangement of proline and glutamine residues that have been found recently within the activation domains of other transcription factors. Expression of the AP-2 clone in bacteria yields a protein that binds to DNA and activates transcription in vitro in a comparable manner to native human AP-2. Transfection of cDNA clones into Drosophila cells indicates that the AP-2 gene product can also activate gene expression in vivo in a DNA template-dependent manner. Expression of endogenous AP-2 is repressed in a hepatoma cell line and stimulated following retinoic-acid-induced differentiation of a human teratocarcinoma cell line. This indicates that AP-2 may be a transcription factor involved in the control of developmentally regulated gene expression.
Williams
T
T
Howard Hughes Medical Institute, Department of Biochemistry, University of California, Berkeley 94720.
Admon
A
A
Lüscher
B
B
Tjian
R
R
D000595:Amino Acid Sequence; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000302:isolation & purification; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics*; D004742:Enhancer Elements, Genetic; D004926:Escherichia coli / Q000235:genetics; D005786:Gene Expression Regulation; D005822:Genetic Vectors; D006801:Humans; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics; D012260:Ribonucleases; D050656:Transcription Factor AP-2; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics*; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D050656:Transcription Factor AP-2; D014157:Transcription Factors; D004247:DNA; D012260:Ribonucleases