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IsomiRs: Expanding the miRNA repression toolbox beyond the seed.

ABSTRACT: MicroRNAs (miRNAs) are a class of small non-coding RNAs that play increasingly appreciated roles in gene regulation. In animals, miRNAs silence gene expression by binding to partially complementary sequences within target mRNAs. It is well-established that miRNAs recognize canonical target sites by base-pairing in the 5'region. However, the development of biochemical methods has identified many novel, non-canonical target sites, suggesting additional modes of miRNA-target association. Here, we review the current knowledge of miRNA-target recognition and how new evidence supports or challenges existing models. We also review the process by which microRNA isoforms achieve functional diversification via modulation of target recognition.

SUBMITTER: Bofill-De Ros X

PROVIDER: S-EPMC6776719 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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IsomiRs: Expanding the miRNA repression toolbox beyond the seed.

Bofill-De Ros Xavier X Yang Acong A Gu Shuo S

Biochimica et biophysica acta. Gene regulatory mechanisms 20190404 4

MicroRNAs (miRNAs) are a class of small non-coding RNAs that play increasingly appreciated roles in gene regulation. In animals, miRNAs silence gene expression by binding to partially complementary sequences within target mRNAs. It is well-established that miRNAs recognize canonical target sites by base-pairing in the 5'region. However, the development of biochemical methods has identified many novel, non-canonical target sites, suggesting additional modes of miRNA-target association. Here, we r ...[more]

PMID: 30953728

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