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Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers
Published on: September 19, 2017
Thermally Induced Transitions of d(G4T4G3) Quadruplexes Can Be Described as Kinetically Driven Processes
Iztok Prislan1, Tomaz Urbic2, Natasa Poklar Ulrih1
1Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia.
Abstract:
DNA sequences that are rich in guanines and can form four-stranded structures are called G-quadruplexes. Due to the growing evidence that they may play an important role in several key biological processes, the G-quadruplexes have captured the interest of several researchers. G-quadruplexes may form in the presence of different metal cations as polymorphic structures formed in kinetically governed processes. Here we investigate a complex polymorphism of d(G4T4G3) quadruplexes at different K+ concentrations. We show that population size of different d(G4T4G3) quadruplex conformations can be manipulated by cooling rate and/or K+ concentration. We use a kinetic model to describe data obtained from DSC, CD and UV spectroscopy and PAGE experiments. Our model is able to describe the observed thermally induced conformational transitions of d(G4T4G3) quadruplexes at different K+ concentrations.
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