Motif independent identification of potential RNA G-quadruplexes by G4RNA screener.

ABSTRACT: G-quadruplex structures in RNA molecules are known to have regulatory impacts in cells but are difficult to locate in the genome. The minimal requirements for G-quadruplex folding in RNA (G?3N1-7?G?3N1-7?G?3N1-7?G?3) is being challenged by observations made on specific examples in recent years. The definition of potential G-quadruplex sequences has major repercussions on the observation of the structure since it introduces a bias. The canonical motif only describes a sub-population of the reported G-quadruplexes. To address these issues, we propose an RNA G-quadruplex prediction strategy that does not rely on a motif definition.We trained an artificial neural network with sequences of experimentally validated G-quadruplexes from the G4RNA database encoded using an abstract definition of their sequence. This artificial neural network, G4NN, evaluates the similarity of a given sequence to known G-quadruplexes and reports it as a score. G4NN has a predictive power comparable to the reported G richness and G/C skewness evaluations that are the current state-of-the-art for the identification of potential RNA G-quadruplexes. We combined these approaches in the G4RNA screener, a program designed to manage and evaluate the sequences to identify potential G-quadruplexes.G4RNA screener is available for download at http://gitlabscottgroup.med.usherbrooke.ca/J-Michel/[e-mail] or [e-mail] or [e-mail] data are available at Bioinformatics online.

SUBMITTER: Garant JM 

PROVIDER: S-EPMC5870565 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature