Sequences at the 3' side of the c-fos SRE mediate gene expression via an Sob1-dependent, TCF-independent pathway.
We previously described a 110-kDa tyrosine phosphoprotein, Sob 1, that regulates formation of the DNA binding complex Band A at the c-fos serum response element (SRE) during T cell activation. Using competition and mutant oligonucleotide analysis, we have determined that both the core CArG box of the c-fos SRE and the 3' sequences flanking the CArG box are necessary for stable Band A complex formation. Moreover, using transient transfection and reporter assays, we show that mutations affecting Band A complex formation in vitro also impaired serum induction of c-fos gene expression in vivo. Since mutation at this site has no effect on SRF binding, our results suggest that in combination with SRE/SRF, Sob 1-regulated factor(s) bind at the 3' side of SRE to form Band A, and this confers maximal serum induction of c-fos gene expression via the SRE.
Omoike
O I
OI
Department of Microbiology, University of Kansas, Lawrence, Kansas, 66045, USA.
Benson
B A
BA
Chan
M A
MA
Benedict
S H
SH
D016475:3T3 Cells; D000818:Animals; D001798:Blood Proteins / Q000494:pharmacology; D005576:Colforsin / Q000494:pharmacology; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005347:Fibroblasts; D005786:Gene Expression Regulation; D051379:Mice; D009154:Mutation; D009687:Nuclear Proteins / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism*; D011485:Protein Binding; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis / Q000235:genetics*; D020218:Response Elements; D026362:Serum Response Factor; D013755:Tetradecanoylphorbol Acetate; D014158:Transcription, Genetic
D001798:Blood Proteins; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D016760:Proto-Oncogene Proteins c-fos; D026362:Serum Response Factor; C489525:p62TCF protein, mouse; D005576:Colforsin; D013755:Tetradecanoylphorbol Acetate