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Contribution of sequence and structure to mRNA-binding of Argonaute/miRNA complexes and degradation of miRNA targets

ABSTRACT: Relative contribution of sequence and structural features to the mRNA-binding of Argonaute/miRNA complexes and the degradation of miRNA targets How miRNAs recognize their target sites is a puzzle that many experimental and computational studies aimed to solve. Several features such as perfect pairing of the miRNA seed, additional pairing in the 3’ region of the miRNA, relative position in the 3’ UTR and the A/U content of the environment of the putative site have been found to be relevant. Here we have used a large number of previously published data sets to assess the power that various sequence and structure features have in distinguishing between putative sites that do and those that do not appear to be functional. We found that although different data sets can give widely different answers when it comes to ranking the relative importance of these features, the sites inferred from most transcriptomics experiments as well as from comparative genomics appear similar at this level. This suggests that miRNA target sites have been selected in evolution on their ability to trigger mRNA degradation. To understand at what step in the miRNA induced response individual features play a role, we further transfected human HEK293 cells with miRNAs and analyzed the association of Argonaute/miRNA complexes with target mRNAs and the degradation of these messages. We found that structural features are only important for Argonaute binding, while sequence features such as the A/U content of the 3’ UTR are important for mRNA degradation. Keywords: IP-array analysis

ORGANISM(S): Homo sapiens

PROVIDER: GSE14537 | GEO | 2009/01/27

SECONDARY ACCESSION(S): PRJNA111621

REPOSITORIES: GEO

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