Identification of non-telomeric G4-DNA binding proteins in human, E. coli, yeast, and Arabidopsis.
G4-DNA binding proteins of E. coli, Saccharomyces cerevisiae, Arabidopsis, and human have been identified by a synthetic non-telomeric G4-DNA oligo 5'-d(ACTGTCGTACTTGATATGGGGGT)-3' using gel mobility shift assays. G4-DNA binding proteins are specific to G4-DNA, a four-stranded guanine-DNA structure. Bound complexes of G4-DNA and proteins were identified in nuclear extracts of all examined organisms in this study. In humans, three different G4-DNA and protein complexes were identified. However, human telomeric G-quadruplex oligo did not compete with G4-DNA oligo in the competition assays, suggesting that the identified G4-DNA binding proteins may be different from the known human telomeric G4-DNA binding proteins. We discovered two complexes of G4-DNA and protein in Arabidopsis identified in mobility shift assays. Interestingly, two complexes of G4-DNA and proteins were identified from E. coli, which have a circular genomic DNA structure. Results of this investigation suggest that non-telomeric G4-DNA structure and its binding proteins may be involved in important functional roles in both prokaryotes and eukaryotes.
Kang
Sang-Gu
SG
Institute of Biotechnology, Yeungnam University, Kyongsan 712- 749, Korea. kangsg@yu.ac.kr
Henderson
Eric
E
D017360:Arabidopsis / Q000737:chemistry*; D001665:Binding Sites; D001667:Binding, Competitive; D017931:DNA Primers / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000032:analysis*; D024202:Electrophoretic Mobility Shift Assay; D004926:Escherichia coli / Q000737:chemistry; D006367:HeLa Cells / Q000737:chemistry; D006801:Humans; D012441:Saccharomyces cerevisiae / Q000737:chemistry*; D029701:Saccharomyces cerevisiae Proteins
D017931:DNA Primers; D004268:DNA-Binding Proteins; C095418:G4p1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins