Regulatory miPEP Open Reading Frames Contained in the Primary Transcripts of microRNAs

Area of Science:

• Molecular Biology
• Genetics
• Evolutionary Biology

Background:

• Primary microRNAs (pri-miRNAs) possess coding properties beyond non-coding RNA production.
• Open reading frames (ORFs) within pri-miRNAs can encode small peptides, termed micropeptide effectors (miPEPs).
• miPEPs have been identified in various plant and animal species, suggesting conserved biological roles.

Purpose of the Study:

• To review available data on the coding potential of pri-miRNAs and the regulatory functions of miPEPs.
• To analyze the molecular mechanisms underlying miPEP activity across different taxa.
• To highlight knowledge gaps and future research directions concerning miPEP evolution and function.

Main Methods:

• Retrospective analysis of published studies on pri-miRNA ORFs and miPEP identification.
• Review of methodologies for identifying pri-miRNA ORFs and their protein products.
• Synthesis of findings on miPEP functional mechanisms and regulatory roles.

Main Results:

• miPEPs are found in diverse plant families and some animal species.
• The molecular mechanisms of miPEP action differ significantly between plants and metazoans.
• miPEPs exhibit varied regulatory effects, including both positive and negative impacts on pri-miRNA/miRNA expression.

Conclusions:

• Significant differences exist in miPEP functions and mechanisms between plants and animals, necessitating taxon-specific investigations.
• Understanding the distribution of miPEPs in non-flowering plants is crucial for elucidating their evolutionary origins.
• Extensive further research is required to fully elucidate the diverse roles of miPEPs and their encoding ORFs in eukaryotic organisms.