Objective Nucleic acids come in many forms aside from the Watson-Crick duplex. For example, guanine-rich DNA strands can form G-quadruplex structures, which have become attractive targets for small molecule ligands. It is now proven that G-quadruplexes can form in cells. Today most biophysical and structural studies on G-quadruplex folding are carried out in dilute aqueous solutions, but recent works suggest that the folding of some G-quadruplexes may differ in a crowded environment such as the cell environment. In the same way, most in vitro ligand binding assays are today carried out in dilute aqueous solutions. The aim of the project is to assess whether and how the folding pathways of G-quadruplexes differs in dilute and crowded conditions, and whether the community should revise the experimental design of ligand screening assays. We will focus on mass spectrometry-based assays, which have the unique advantage to give a direct read-out of ligand binding stoichiometry, quantity, and the variety of structural ensembles hiding behind the free and bound nucleic acid. The research program involves (1) developing mass spectrometry in more “native” conditions in the sense that we will add co-solutes to mimic cellular crowding, (2) comparing the G-quadruplex folding pathways in dilute and crowded conditions, by combining for the first time mass spectrometry, nuclear magnetic resonance, and single-molecule FRET (Förster resonance energy transfer), and (3) evaluating the impact of crowding on both traditional melting assays and mass spectrometry-based ligand screening assays. Our project will contribute to unveil fundamental principles of nucleic acid folding. It will also foster collaboration between three European institutes specialized in complementary biophysical and structural approaches to study G-quadruplexes. Finally, our project will also contribute to society by improving analytical approaches that are highly relevant to pharmacology. Fields of science natural sciencesbiological sciencesbiochemistrybiomoleculesnucleic acidsnatural sciencesbiological sciencesgeneticsDNAnatural scienceschemical sciencesanalytical chemistrymass spectrometrymedical and health sciencesbasic medicinepharmacology and pharmacy Programme(s) H2020-EU.1.3. - EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions Main Programme H2020-EU.1.3.2. - Nurturing excellence by means of cross-border and cross-sector mobility Topic(s) MSCA-IF-2017 - Individual Fellowships Call for proposal H2020-MSCA-IF-2017 See other projects for this call Funding Scheme MSCA-IF-EF-ST - Standard EF Coordinator INSTITUT NATIONAL DE LA SANTE ET DE LA RECHERCHE MEDICALE Net EU contribution € 173 076,00 Address RUE DE TOLBIAC 101 75654 Paris France See on map Region Ile-de-France Ile-de-France Paris Activity type Research Organisations Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Total cost € 173 076,00
