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Updated: Jan 26, 2026
06:16
mirMachine: A One-Stop Shop for Plant miRNA Annotation
Published on: May 1, 2021
2.9K
IsomiRs: Expanding the miRNA repression toolbox beyond the seed
Xavier Bofill-De Ros1, Acong Yang1, Shuo Gu1
1RNA Mediated Gene Regulation Section, RNA Biology Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, United States.
Summary
MicroRNAs (miRNAs) regulate gene expression by binding to messenger RNAs. Recent discoveries reveal non-canonical binding sites, expanding our understanding of miRNA-target interactions and functional diversification.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- MicroRNAs (miRNAs) are small non-coding RNAs crucial for gene regulation.
- miRNAs typically silence gene expression via binding to target mRNAs in animals.
- Canonical miRNA recognition involves base-pairing in the 5' region of target sites.
Purpose of the Study:
- To review current knowledge on microRNA-target recognition mechanisms.
- To discuss novel findings that support or challenge existing models of miRNA binding.
- To explore how microRNA isoforms diversify function through target recognition modulation.
Main Methods:
- Literature review of biochemical and genetic studies on miRNA function.
- Analysis of data identifying canonical and non-canonical miRNA target sites.
- Synthesis of evidence regarding miRNA-isoform-specific target interactions.
Main Results:
- Biochemical methods have identified numerous non-canonical miRNA target sites.
- Evidence suggests diverse modes of miRNA-target association beyond canonical binding.
- MicroRNA isoforms exhibit distinct target recognition profiles, leading to functional diversification.
Conclusions:
- The understanding of miRNA-target recognition is evolving beyond canonical models.
- Non-canonical interactions represent a significant mechanism in miRNA-mediated gene regulation.
- MicroRNA isoforms play a key role in fine-tuning gene expression through varied target recognition.
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