Activation of junB by PKC and PKA signal transduction through a novel cis-acting element.
The product of the junB gene, a gene homologous to the proto-oncogene c-jun, is a component of transcription factor AP-1. JunB expression is modulated by a wide variety of extracellular stimuli, such as serum, growth factors, phorbol esters (TPA) and activators of protein kinase A (PKA). In order to study the molecular basis of this complex regulation, we have cloned the mouse junB gene from a genomic testis library, and characterized the junB promoter. Here we show that the junB promoter is activated by serum, TPA, and activated PKA. Sequences located between -91 and -44 are necessary for induction. These sequences contain a CAAT box, a G-C rich region and a previously undescribed inverted repeat (IR). The IR element can mediate induction by TPA and PKA when coupled to a heterologous promoter, and specifically binds a protein of 110 kD.
de Groot
R P
RP
Hubrecht Laboratory, Netherlands Institute for Developmental Biology, Utrecht.
Auwerx
J
J
Karperien
M
M
Staels
B
B
Kruijer
W
W
D000818:Animals; D001483:Base Sequence; D001769:Blood; D015152:Blotting, Northern; D003432:Cross-Linking Reagents; D004268:DNA-Binding Proteins / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D010957:Plasmids; D011401:Promoter Regions, Genetic; D011493:Protein Kinase C / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism*; D016755:Proto-Oncogene Proteins c-jun; D012313:RNA / Q000032:analysis; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics*; D014162:Transfection; D014407:Tumor Cells, Cultured
D003432:Cross-Linking Reagents; D004268:DNA-Binding Proteins; D016755:Proto-Oncogene Proteins c-jun; D014157:Transcription Factors; D012313:RNA; D011494:Protein Kinases; D011493:Protein Kinase C