The nickel(II) complex of guanidinium phenyl porphyrin, a specific G-quadruplex ligand, targets telomeres and leads to POT1 mislocalization in culture cells

• DOI: 10.1007/s00775-015-1260-8
• Publication Date: 2015-04-06T06:20:02Z
• Authors: Laurent Sabater; Marie-Laure Nicol...; Aurore De Rache; Enora Prado; Jérôme Dejeu; Oriane Bombarde; Joris Lacroix; Patrick Calsou; Eric Defrancq; Jean-Louis Mergny; Dennis Gomez; Geneviève Pratviel
• Keywords: Shelterin; Cationic polymerization; G-quadruplex; Derivative (finance)

With the aim of finding selective and biologically active G-quadruplex ligands, modified porphyrin with bulky cationic substituents, meso-5,10,15,20-tetrakis(4-guanidinophenyl)porphyrin tetrahydrochloride, referred to as guanidinium phenyl porphyrin, was prepared. The corresponding nickel(II) and cobalt(III) metallated porphyrins were also synthesized. Interaction with quadruplexes was examined by means of fluorescence resonance energy transfer melting and surface plasmon resonance-based assays: the three compounds proved to bind to G-quadruplex DNA in a similar and highly selective way. Guanidinium phenyl porphyrin and its nickel(II) metallated derivative exhibit moderate cytotoxicity toward cells in culture. Strikingly, the nickel porphyrin derivative was able to displace hPOT1 shelterin protein from telomeres in human cells. Nickel(II) guanidinium phenyl porphyrin, a cationic bulky porphyrin is a powerful specific G-quadruplex DNA ligand. It enters the cells and induces shelterin modification.