Dynamic roles for G4 DNA in the biology of eukaryotic cells

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Recent advances have made a persuasive case for the existence of G4 DNA in living cells, but what—if any—are its functions? Experiments have established how G4 DNA may contribute to the biology of eukaryotic cells, and genomic analysis has identified new ways in which the potential to form G4 DNA may influence gene regulation and genomic stability. This Perspective highlights those advances and identifies some key open questions.

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Figure 1: G-quartets and G4 DNA.
Figure 2: Formation of G4 DNA upon replication.
Figure 3: G4 DNA at telomeres.
Figure 4: G-rich S regions are targets of immunoglobulin heavy-chain class switch recombination.
Figure 5: G-loop formed in a transcribed G-rich region is bound by MutSα.


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I thank members of my laboratory for provocative discussions, and the US National Institutes of Health for supporting our research on G4 DNA (R01 GM65988) and switch recombination (R01 GM39799).

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