Mechanisms of recipient-cell uptake of extracellular microRNAs

Investigate and define the cellular mechanisms by which recipient cells internalize extracellular microRNAs, distinguishing among macropinocytosis, clathrin-mediated endocytosis, scavenger receptor class B type 1 (SR-B1)-mediated uptake of HDL-bound microRNAs, direct membrane fusion, and gap junction transfer.

Background

Although several routes of uptake have been proposed for extracellular microRNAs—including endocytosis for exosomes and SR-B1-mediated uptake for HDL-bound microRNAs—the field lacks comprehensive in vivo validation and mechanistic delineation across cell types.

Clarifying uptake mechanisms will enable accurate modeling of intercellular RNA signaling and guide therapeutic delivery strategies.