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Stimulation of ribosomal frameshifting by RNA G-quadruplex structures.

ABSTRACT: Guanine-rich sequences can fold into four-stranded structures of stacked guanine-tetrads, so-called G-quadruplexes (G4). These unique motifs have been extensively studied on the DNA level; however, exploration of the biological roles of G4s at the RNA level is just emerging. Here we show that G4 RNA when introduced within coding regions are capable of stimulating -1 ribosomal frameshifting (-1 FS) in vitro and in cultured cells. Systematic manipulation of the loop length between each G-tract revealed that the -1 FS efficiency positively correlates with G4 stability. Addition of a G4-stabilizing ligand, PhenDC3, resulted in higher -1 FS. Further, we demonstrated that the G4s can stimulate +1 FS and stop codon readthrough as well. These results suggest a potentially novel translational gene regulation mechanism mediated by G4 RNA.

SUBMITTER: Yu CH

PROVIDER: S-EPMC3919603 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

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Stimulation of ribosomal frameshifting by RNA G-quadruplex structures.

Yu Chien-Hung CH Teulade-Fichou Marie-Paule MP Olsthoorn René C L RC

Nucleic acids research 20131030 3

Guanine-rich sequences can fold into four-stranded structures of stacked guanine-tetrads, so-called G-quadruplexes (G4). These unique motifs have been extensively studied on the DNA level; however, exploration of the biological roles of G4s at the RNA level is just emerging. Here we show that G4 RNA when introduced within coding regions are capable of stimulating -1 ribosomal frameshifting (-1 FS) in vitro and in cultured cells. Systematic manipulation of the loop length between each G-tract rev ...[more]

PMID: 24178029

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