Structural Comparisons of PEI/DNA and PEI/siRNA Complexes Revealed with Molecular Dynamics Simulations

摘要: Polyplexes composed of polyethyleneimine (PEI) and DNA or siRNA have attracted great attention for their use in gene therapy. Although many physicochemical characteristics these polyplexes remain unknown, PEI/DNA complexes been repeatedly shown to be more stable than PEI/siRNA counterparts. Here, we examine potential causes this difference using atomistic molecular dynamics simulations complexation between linear PEI duplexes containing the same number bases. The two types are stabilized by similar interactions, as amines primarily interact with nucleic acid phosphate groups but also occasionally groove atoms both acids. However, interactions is greater comparable complexes, protonated being particularly enhanced. These results indicate that structural differences may play a role increased stabilit...