Figure 2.

Detection of GVBQ in the wild G-rich ssDNA from the PDGFR-β promoter NHE region by exonuclease digestion. (A) G4-forming sequence and its modifications from human PDGFR-β gene promoter. The G-tracts of wild DNA sequences (WT) are highlighted in red and mutations are highlighted in cyan. (B) Formation of G-quadruplexes protect the DNA from being hydrolyzed from the 3′ end by T4 DNA polymerase. (C) Formation of G-quadruplexes protected the DNA from being hydrolyzed from the 5′ end by RecJ exonuclease.