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Retro-miRs: novel and functional miRNAs originating from mRNA retrotransposition
Rafael L V Mercuri1,2, Helena B Conceição1,2, Gabriela D A Guardia1
1Hospital Sirio-Libanes, São Paulo, 01308-060, Brazil.
Mobile DNA
|September 8, 2023
Summary
New primate-specific microRNAs (miRNAs) called retro-miRs originate from retrocopied messenger RNAs. These retro-miRs are expressed, conserved, target important genes, and are implicated in cancer development.
Area of Science:
- Evolutionary biology
- Molecular biology
- Genomics
Background:
- Retrocopies are significant sources of evolutionary novelty.
- MicroRNAs (miRNAs) are crucial post-transcriptional regulators.
- The precise origins and evolution of miRNAs remain incompletely understood.
Purpose of the Study:
- To comprehensively investigate the origination of novel miRNAs from retroduplicated mRNA sequences, termed retro-miRs.
- To characterize the conservation, expression, and functional roles of these retro-miRs.
Main Methods:
- Identification and analysis of retro-miRs derived from mRNA retrocopies.
- Determination of retro-miRs' origins (de novo or duplication).
- Assessment of retro-miRs' conservation across primate species and their expression patterns.
Main Results:
- 17 retro-miRs were identified, originating from mRNA retrocopies.
- Four retro-miRs showed de novo origins, while 13 were integrated into existing exon regions.
- Retro-miRs were primate-specific, with some conserved across primates and others unique to humans.
- All identified retro-miRs were expressed and targeted genes involved in crucial biological processes, including CNS functions.
- Retro-miRs demonstrated potential oncogenic roles by targeting cancer-related genes and were overexpressed in specific cancers.
Conclusions:
- mRNA retrotransposition is a primary mechanism for generating novel primate miRNAs (retro-miRs).
- These retro-miRs are expressed, conserved, and possess functional target genes.
- Retro-miRs play significant roles in cellular functions and cancer pathogenesis.
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