A dynamic i-motif with a duplex stem-loop in the long terminal repeat promoter of the HIV-1 proviral genome modulates viral transcription.

ABSTRACT: I-motifs are non-canonical nucleic acids structures characterized by intercalated H-bonds between hemi-protonated cytosines. Evidence on the involvement of i-motif structures in the regulation of cellular processes in human cells has been consistently growing in the recent years. However, i-motifs within non-human genomes have never been investigated. Here, we report the characterization of i-motifs within the long terminal repeat (LTR) promoter of the HIV-1 proviral genome. Biophysical and biochemical analysis revealed formation of a predominant i-motif with an unprecedented loop composition. One-dimensional nuclear magnetic resonance investigation demonstrated formation of three G-C H-bonds in the long loop, which likely improve the structure overall stability. Pull-down experiments comb

SUBMITTER: Ruggiero E 

PROVIDER: S-EPMC6868428 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature