Crystal structure of the heterodimeric bZIP transcription factor c-Fos-c-Jun bound to DNA.
The Fos and Jun families of eukaryotic transcription factors heterodimerize to form complexes capable of binding 5'-TGAGTCA-3' DNA elements. We have determined the X-ray crystal structure of a heterodimer of the bZIP regions of c-Fos and c-Jun bound to DNA. Both subunits form continuous alpha-helices. The carboxy-terminal regions form an asymmetric coiled-coil, and the amino-terminal regions make base-specific contacts with DNA in the major groove. Comparison of the two crystallographically distinct protein-DNA complexes show that the coiled-coil is flexibly joined to the basic regions and that the Fos-Jun heterodimer does not recognize the asymmetric 5'-TGAGTCA-3' recognition element in a unique orientation. There is an extensive network of electrostatic interactions between subunits within the coiled-coil, consistent with proposals that these interactions determine preferential formation of the heterodimer over either of the homodimers.
Glover
J N
JN
Howard Hughes Medical Institute, Harvard University, Cambridge, Massachusetts 02138.
Harrison
S C
SC
D000595:Amino Acid Sequence; D001483:Base Sequence; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011485:Protein Binding; D011487:Protein Conformation; D016760:Proto-Oncogene Proteins c-fos / Q000737:chemistry* / Q000378:metabolism; D016755:Proto-Oncogene Proteins c-jun / Q000737:chemistry* / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000378:metabolism
D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D018808:Transcription Factor AP-1; D004247:DNA