Kinetic studies of Fos.Jun.DNA complex formation: DNA binding prior to dimerization.
The bZIP proteins Fos and Jun bind DNA rapidly and with high affinity, forming a heteromeric complex that mediates activated transcription. Here we use stopped-flow fluorescence resonance energy transfer (FRET) to study the kinetic pathway by which Fos.Jun. DNA complexes assemble. Though dimerization of Fos and Jun occurs rapidly in the absence of DNA, the rate of dimerization is enhanced in the presence of DNA. Global analysis of the kinetic data shows that the favored DNA binding pathway is one is which the two protein monomers bind DNA sequentially and assemble their dimerization interface while bound to DNA.
Kohler
J J
JJ
Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, USA.
Schepartz
A
A
D000595:Amino Acid Sequence; D004247:DNA / Q000737:chemistry* / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D019281:Dimerization; D004735:Energy Transfer; D005452:Fluoresceins / Q000737:chemistry; D005454:Fluorescence Polarization; D005456:Fluorescent Dyes / Q000737:chemistry; D006801:Humans; D007700:Kinetics; D008956:Models, Chemical; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D016760:Proto-Oncogene Proteins c-fos / Q000737:chemistry* / Q000378:metabolism*; D016755:Proto-Oncogene Proteins c-jun / Q000737:chemistry* / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
D004268:DNA-Binding Proteins; D005452:Fluoresceins; D005456:Fluorescent Dyes; D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D004247:DNA