Structure and Dynamics of DNA and RNA Double Helices Obtained from the CCG and GGC Trinucleotide Repeats.

ABSTRACT: Expansions of both GGC and CCG sequences lead to a number of expandable, trinucleotide repeat (TR) neurodegenerative diseases. Understanding of these diseases involves, among other things, the structural characterization of the atypical DNA and RNA secondary structures. We have performed molecular dynamics simulations of (GCC) _n and (GGC) _n homoduplexes in order to characterize their conformations, stability, and dynamics. Each TR has two reading frames, which results in eight nonequivalent RNA/DNA homoduplexes, characterized by CpG or GpC steps between the Watson-Crick base pairs. Free energy maps for the eight homoduplexes indicate that the C-mismatches prefer anti-anti conformations, while G-mismatches prefer anti-syn conformations. Comparison between three modific

SUBMITTER: Pan F 

PROVIDER: S-EPMC6475210 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature