Multiple mRNA targets of exosomal microRNAs

Multiple mRNA targets of exosomal microRNAs (miRNAs) represent a broad class of genetic elements regulated by the horizontal transfer of RNA via extracellular vesicles. Exosomes, which are 30-150 nm vesicles of endocytic origin, sequester miRNAs to protect them from RNase-mediated degradation and facilitate their delivery to specific recipient cells (Kalluri & LeBleu, 2020). Upon entry into the cytoplasm, these miRNAs function as part of the RNA-induced silencing complex (RISC) to identify and bind complementary sequences, primarily within the 3' untranslated regions (UTRs) of target mRNAs (Bartel, 2009). This interaction leads to either the inhibition of translation or the direct cleavage of the mRNA transcript, thereby modulating the proteome of the recipient cell. This regulatory axis is heavily implicated in cancer progression, where tumor-derived exosomes can reprogram stromal cells or suppress immune responses by targeting mRNAs involved in apoptosis and cell cycle control (Whiteside, 2016). Therapeutic strategies involving this pathway often focus on using synthetic miRNA mimics or antagomirs packaged into bioengineered exosomes to restore or inhibit specific gene expression patterns in diseased tissues (Mendt et al., 2019). However, the inherent ability of a single miRNA to target hundreds of different mRNAs poses a significant challenge for achieving high therapeutic specificity and avoiding off-target toxicity.

Other names

Exosomal miRNA targetsmRNA targets of extracellular vesicle-derived miRNAsExosomal microRNA-regulated mRNAs

Post-transcriptional gene silencing through the binding of exosomal microRNAs to the 3' untranslated regions (UTRs) of target mRNAs, resulting in mRNA degradation or translational inhibition (Bartel, 2009).