Selection of a high-affinity DNA pool for a bZip protein with an out-of-phase alignment of the basic region relative to the leucine zipper.
bZip transcription factors contain two regions that are required for DNA binding: a leucine zipper dimerization domain and a highly charged basic region that directly contacts DNA. The spacing between these subdomains is strictly conserved, and changes in this spacing result in a loss of function. Using an in vitro selection strategy, we have investigated the ability of a bZip protein with incorrect spacing between these two regions to bind specifically to DNA. Surprisingly, we find that although such a protein does not bind to its predicted site, it is possible to isolate a pool of DNAs that bind with very similar affinity to that of GCN4 for its optimum DNA site.
Lee
Y
Y
Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA.
Gurnon
D G
DG
Hollenbeck
J J
JJ
Oakley
M G
MG
D000595:Amino Acid Sequence; D050976:Basic-Leucine Zipper Transcription Factors; D001665:Binding Sites; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D005656:Fungal Proteins / Q000737:chemistry / Q000378:metabolism; D051790:G-Box Binding Factors; D016350:Leucine Zippers; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000378:metabolism; D010446:Peptide Fragments; D011485:Protein Binding; D011487:Protein Conformation; D011494:Protein Kinases / Q000737:chemistry / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D013329:Structure-Activity Relationship; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D015003:Yeasts
D050976:Basic-Leucine Zipper Transcription Factors; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D051790:G-Box Binding Factors; D009838:Oligodeoxyribonucleotides; D010446:Peptide Fragments; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D004247:DNA; D011494:Protein Kinases