Furan based cyclic homo-oligopeptides bind G-quadruplex selectively and repress c-MYC transcription

We demonstrate the synthesis and selective binding of two novel furan based tricyclic homo-oligopeptides to G-quadruplex and using Real Time PCR show its repressive effect on c-MYC transcription. CD spectroscopy and FRET melting studies show that these ligands can induce G-quadruplex structures in the G rich 22 mer c-MYC DNA sequence and further stabilize the structure. Using real time polymerase chain reaction we observed that up to 70% downregulation of c-MYC transcripts upon ligand treatment in HeLa cells.