Skip to main content
. 2021 Oct 7;9:740303. doi: 10.3389/fcell.2021.740303

FIGURE 3.

FIGURE 3

Secretion of miRNAs into the extracellular environment. Primary microRNA (pri-miRNAs) are transcribed by RNA polymerase II and then processed by Drosha into precursor-miRNAs (pre-miRNAs). Exportin5 transfers these pre-miRNAs from the nucleus to the cytoplasm, where Dicer converts them into mature miRNAs. Mature miRNAs can be selectively incorporated into extracellular vesicles (EVs) (exosomes and microvesicles) or linked to the Argonaute 2 (Ago2) protein and released into the extracellular environment. Alternatively, they can be attached to high-density lipoprotein (HDL) or contained in apoptotic bodies and then released into the extracellular environment.