Promotion of parallel DNA quadruplexes by a yeast telomere binding protein: a circular dichroism study.
Repressor-activator protein 1 (RAP1) has an essential role in the maintenance of yeast telomeres. Yeast telomeric DNA consists of simple repeated G-rich sequences that are bound by RAP1. We have found that RAP1, in addition to its known binding activity for double-stranded DNA, interacts with the G-rich strand containing guanine base (G)-tetrads. We show here using circular dichroism spectroscopy that RAP1 promotes the formation of one particular type of DNA quadruplex, parallel G4-DNA. Furthermore, RAP1 is able to bind to both preformed parallel and antiparallel DNA quadruplexes. These results have implications for the possible use of DNA quadruplexes in telomere-telomere association in vivo.
Giraldo
R
R
Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom.
Suzuki
M
M
Chapman
L
L
Rhodes
D
D
D000818:Animals; D001483:Base Sequence; D002942:Circular Dichroism; D004247:DNA / Q000378:metabolism*; D004271:DNA, Fungal / Q000378:metabolism*; D054856:G-Quadruplexes; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006147:Guanine / Q000378:metabolism; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation / Q000187:drug effects; D009838:Oligodeoxyribonucleotides / Q000378:metabolism; D016813:Oxytricha / Q000235:genetics; D011188:Potassium / Q000494:pharmacology; D011485:Protein Binding; D012091:Repetitive Sequences, Nucleic Acid; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D016615:Telomere / Q000378:metabolism*; D020668:rap GTP-Binding Proteins
D004271:DNA, Fungal; D009838:Oligodeoxyribonucleotides; D006147:Guanine; D004247:DNA; D019204:GTP-Binding Proteins; D020668:rap GTP-Binding Proteins; D011188:Potassium