A two-quartet G-quadruplex topology of human KIT2 is conformationally selected by a perylene derivative - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Biochimie Année : 2020

A two-quartet G-quadruplex topology of human KIT2 is conformationally selected by a perylene derivative

Résumé

G-quadruplexes are promising targets for innovative anticancer therapy. Hence, many efforts are being made to find selective ligands. Drug design is often based on the available high-resolution structures, obtained for the thermodynamically stable forms. However, the complexity of the G-quadruplex folding landscape has clearly emerged in recent years, with the discovery of intermediate conformations that persist on the second to the minute time scale. In the case of the KIT2 G-quadruplex forming sequence, found within human c-KIT promoter, we recently identified a long-lived folding intermediate, characterized by guanine stacking in alternating orientation (as determined by circular dichroism). Given the rate of transcriptional processes, a physiological role of this arrangement should not be excluded. In the present study, we applied circular dichroism (CD) spectroscopy, native electrospray ionization mass spectrometry (ESI-MS) and electrophoretic mobility shift assays (EMSA) to show that a perylene derivative (K20) selects this topology. Interestingly, ESI-MS spectra revealed the presence of a single specifically coordinated K+ ion in the structure, which is thus presumably composed of only two consecutive G-quartets. The parent ligand PIPER failed to promote the same conformational selection, which is therefore a process strictly dependent on the perylene side chains composition. The greater affinity of K20 for the two-quartet antiparallel topology, compared to PIPER, was finally corroborated by evaluating their binding to the KIT∗ G-quadruplex, which is also found within the human promoter of c-KIT.
Fichier principal
Vignette du fichier
S0300908420302212.pdf (958.68 Ko) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-03321840 , version 1 (26-09-2022)

Licence

Paternité - Pas d'utilisation commerciale

Identifiants

Citer

Silvia Ceschi, Eric Largy, Valérie Gabelica, Claudia Sissi. A two-quartet G-quadruplex topology of human KIT2 is conformationally selected by a perylene derivative. Biochimie, 2020, 179, pp.77-84. ⟨10.1016/j.biochi.2020.09.015⟩. ⟨hal-03321840⟩
17 Consultations
13 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More