Use of miRNAs as Biomarkers in Sepsis

Figure 1

miRNA biogenesis mechanism. miRNA synthesis begins with RNA polymerase II action on protein coding genes. (a) Through the transformation phenomenon of the miRNAs genes, pri-miRNA is forming. (b) By the action of RNase III endonuclease (Drosha) and of the DiGeorge Syndrome Critical Region 8 (DGCR8) cofactor, the pre-miRNA is forming. (c) Through transporting protein Exportin-5, pre-miRNA is transferred from the nucleus into the cytoplasm. (d) In the cytoplasm pre-miRNA is attacked by second RNase III endonuclease (Dicer) and transactivator RNA binding protein forming mature miRNA (double-stranded) and (passenger strand). In what follows, mature miRNA induced silencing is taken in complex (RISC). RISC complex contains mature miRNA and protein Argonaute 2 (AGO) that confers increased stability of the complex. After this, miRNAs are released from the cell by two mechanisms: active release (microvesicles, exosomes, and high density lipoprotein particles) and passive release (apoptotic bodies).