DNA Metastability and Biological Regulation: Conformational Dynamics of Metastable Ω-DNA Bulge Loops
journal contributionposted on 25.04.2007, 00:00 by Jens Völker, Horst H. Klump, Kenneth J. Breslauer
Dynamic interchange between DNA conformations, including metastable states, can be of importance to biological function. In this study, we use a combination of spectroscopic and calorimetric techniques to detect and characterize kinetically trapped, metastable states in strand exchange and strand displacement reactions for bulge loop DNA conformations, here referred to as Ω-DNAs. We show that such metastable, Ω-DNA bulge loop states can stably coexist below 50 °C, while rearranging irreversibly at elevated temperatures to thermodynamically more stable states. Such dynamic interchange between metastable and globally stable DNA conformational states can be of importance in biological regulatory mechanisms.