(253s) Potential of Mean Force of siRNA and Pmal: Molecular Dynamics and Theoretical Analysis

Authors: 
Lu, D., Key Lab of Industrial Biocatalysis, Ministry of Education, Tsinghua University
Wu, J., University of California Riverside
Effective delivery of siRNA is a significant problem which involves the health of human beings[1-2]. PMAL (Poly (maleic anhydride-alt-1-decene) substituted with 3-(Dimethylamino) propylamine) is introduced to facilitate siRNA delivery because of amphipathy and biological compatibility[3-4]. The interaction between siRNA and the carrier is the basic problem that determines stability of complex and transmembrane process[5-6]. However, itâ??s still lack of theory describing the complexation process though many simulation results elaborate the interaction of siRNA and carrier[7]. In this work, the effect of charge of PMAL on PMF curves is investigated with molecular dynamics. Based on the MD results, Manning theory is used to explain counterion condensation while Debye-Huckel approximation is employed to predict PMF. The extent of theory will be broadened by the success of this case and itâ??s a sign that simple theory can be applied to handle the biochemical issues.

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