Weak temporal signals can synchronize and accelerate the transition dynamics of biopolymers under tension.
In addition to thermal noise, which is essential to promote conformational transitions in biopolymers, the cellular environment is replete with a spectrum of athermal fluctuations that are produced from a plethora of active processes. To understand the effect of athermal noise on biological processes, we studied how a small oscillatory force affects the thermally induced folding and unfolding transition of an RNA hairpin, whose response to constant tension had been investigated extensively in both theory and experiments. Strikingly, our molecular simulations performed under overdamped condition show that even at a high (low) tension that renders the hairpin (un)folding improbable, a weak external oscillatory force at a certain frequency can synchronously enhance the transition dynamics of RNA hairpin and increase the mean transition rate. Furthermore, the RNA dynamics can still discriminate a signal with resonance frequency even when the signal is mixed among other signals with nonresonant frequencies. In fact, our computational demonstration of thermally induced resonance in RNA hairpin dynamics is a direct realization of the phenomena called stochastic resonance and resonant activation. Our study, amenable to experimental tests using optical tweezers, is of great significance to the folding of biopolymers in vivo that are subject to the broad spectrum of cellular noises.
Department of Physics and POSTECH Center for Theoretical Physics, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
Won Kyu
WK
Kim
Changbong
C
Hyeon
Wokyung
W
Sung
D001696:Biomechanical Phenomena; D001703:Biophysics; D001704:Biopolymers / Q000737:chemistry*; D006358:Hot Temperature; D008956:Models, Chemical; D008968:Molecular Conformation; D056004:Molecular Dynamics Simulation; D034741:RNA, Small Interfering / Q000737:chemistry*
D001704:Biopolymers; D034741:RNA, Small Interfering