Multi-strand binding of nuclear factors to a repressor of mouse mammary tumor virus transcription can be distinguished kinetically.
NRE1 is a DNA sequence element in the long terminal repeat of mouse mammary tumor virus that represses viral transcription in mature T cells. In addition to double-stranded binding activity, factors in Jurkat T cell nuclear extracts bind specifically to each of the two single-strands of NRE1. Here we show that binding to the three forms of NRE1 can be distinguished kinetically. The on rates for double, upper and lower-strand NRE1 binding were 1.5, 3, and 11 min, respectively. Binding was extremely stable with off-rates varying from 30 and 60 min for double and upper-strand binding to 12 h for lower-strand binding. In addition, a truncated form of NRE1 that is only bound as a double-strand was observed to have an on rate of binding of 4 min and an off rate of 4 h.
Rodda
D J
DJ
Department of Medicine, University of Ottawa, Loeb Institute for Medical Research, Ontario, Canada.
Giffin
W
W
Haché
R J
RJ
D001483:Base Sequence; D002460:Cell Line; D004277:DNA, Single-Stranded / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism*; D009838:Oligodeoxyribonucleotides; D011485:Protein Binding; D012045:Regulatory Sequences, Nucleic Acid; D012091:Repetitive Sequences, Nucleic Acid; D014158:Transcription, Genetic
D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D009838:Oligodeoxyribonucleotides