Additional stories of microRNAs

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• MicroRNAs (miRNAs) are key regulators of eukaryotic gene expression, traditionally understood to control cellular events via targeting coding transcripts.
• Conventional miRNA mechanisms involve specific enzymes for maturation and inhibition through binding to 3'-untranslated regions of target transcripts.

Purpose of the Study:

• To review recent discoveries in miRNA biosynthesis and function.
• To highlight noncanonical miRNA mechanisms and newly identified regulatory processes.

Main Methods:

• Literature review of recent studies on miRNA biogenesis and function.
• Synthesis of information on novel miRNA-related mechanisms and small RNA classes.

Main Results:

• Established miRNA pathways are more complex than previously thought, with numerous exceptions.
• New insights include noncanonical miRNA functions, novel biogenesis pathways, miRNA-sized small RNAs, miRNA methylation, and intercellular miRNA signaling.

Conclusions:

• Recent findings significantly expand the understanding of miRNA regulatory roles.
• The complexity of miRNA biology necessitates a re-evaluation of traditional models.