Exosomal microRNA (exo-miRNA)

Exosomal microRNAs (exo-miRNAs) are a class of small, non-coding RNA molecules typically 19-25 nucleotides in length that are packaged into exosomes for intercellular communication (Valadi et al., 2007, Nature Cell Biology). These molecules are secreted by various cell types into the extracellular environment and are protected from enzymatic degradation by the lipid bilayer of the exosome (Zhang et al., 2015, Nature). Upon uptake by recipient cells, exo-miRNAs function as key regulators of gene expression by binding to complementary sequences on target messenger RNAs (mRNAs), leading to translational repression or mRNA cleavage (NIH/NCBI). In the context of disease, exo-miRNAs are frequently dysregulated and contribute to the pathogenesis of cancer, cardiovascular disorders, and neurodegenerative conditions by modulating the microenvironment and promoting processes like angiogenesis or immune evasion (PubMed). As therapeutic targets, they can be modulated using antisense oligonucleotides to inhibit oncogenic miRNAs or supplemented with miRNA mimics to restore tumor-suppressive functions (ClinicalTrials.gov). Furthermore, their stability in biofluids makes them highly attractive candidates for non-invasive liquid biopsy biomarkers in precision medicine. The development of exosome-based delivery systems for these miRNAs represents a significant frontier in targeted drug delivery and regenerative medicine.

Other names

Exosome-derived microRNAExosomal miRNAExtracellular vesicle-contained microRNAexo-miR

Exosomal microRNAs act by binding to the 3' untranslated region (UTR) of target mRNAs within recipient cells, leading to mRNA degradation or translational inhibition through the RNA-induced silencing complex (RISC) (NIH/NCBI).