Characterization of a Max:DNA complex by cross-linking to photoactive oligonucleotides.
The structure of the Max:DNA complex was investigated by cross-linking Max to a series of photoactive oligonucleotides. A single photoactive aryl azide was introduced into oligonucleotides at defined positions downstream from the specific CACGTG binding site. Purified Max homodimers bound to and were cross-linked to oligonucleotides containing a photoactive group either 2, 5, 8, or 11 bp downstream from the binding site. Further analysis revealed that an amino-terminal chymotryptic peptide of Max was cross-linked to the oligonucleotide containing a photoactive probe 11 bp downstream from the specific binding site. This result is consistent with the recent crystal structure of the Max:DNA complex (Ferré-D'Amaré et al., 1993) and further suggests that amino acid residues near the amino-terminus of Max are in close proximity to a region of DNA that is separated from the core binding site by one turn of the double helix.
Department of Microbiology, Medical College of Wisconsin, Milwaukee 53226.
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Mullen
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Wang
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D000595:Amino Acid Sequence; D001386:Azides / Q000737:chemistry; D001483:Base Sequence; D050976:Basic-Leucine Zipper Transcription Factors; D001665:Binding Sites; D003001:Cloning, Molecular; D003432:Cross-Linking Reagents; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics; D018257:Helix-Loop-Helix Motifs; D008969:Molecular Sequence Data; D009841:Oligonucleotides / Q000737:chemistry / Q000378:metabolism*; D010777:Photochemistry; D014157:Transcription Factors
D001386:Azides; D050976:Basic-Leucine Zipper Transcription Factors; D003432:Cross-Linking Reagents; D004268:DNA-Binding Proteins; C067850:Myc associated factor X; D009841:Oligonucleotides; D014157:Transcription Factors; D004247:DNA