G-quadruplex are nucleic acid secondary structures that typically formed within guanine-rich DNA sequences. The chemical mapping of G4 by B-CePs aims at the in vitro characterization of G4, and allows the identification of the specific guanines forming the G-tetrads. The identification and the experimental validation of G4s within potential G-quadruplex-forming sequences is a biologically relevant issue, which is currently addressed primary through computational tools.
To support such predictions and detect the unpredicted G4, chemical mapping by B-CePs represents an accessible method to identify G4 in DNA sequences. The chemical mapping by B-CePs is a convenient alternative to the widely used dimethyl sulfate footprinting protocol for the characterization of G-quadruplex. The key advantage by B-CePs is that it reduces the number of steps in the protocol and it reduces the initial amount of the DNA substrate.
The chemical mapping by B-CePs is described here with the TBA sequence as a proof of concept. The protocol will lead to new experiments applicable to any other potential G-quadruplex-forming sequence exploring both DNA and RNA constructs.