MicroRNA 122-5p (miR-122-5p)

MicroRNA 122–5p is a highly conserved, liver-specific microRNA that plays a central role in the regulation of gene expression at the post-transcriptional level. It is one of the most abundant microRNAs in adult human liver tissue—accounting for up to 72% of total hepatic miRNAs—and is essential for maintaining normal lipid metabolism. Its expression is regulated by transcription factors such as HNF4α. Functionally, miR‑122–5p modulates fatty acid metabolism, influences circadian rhythm genes, regulates cell proliferation/apoptosis pathways (including c-Abl/HDAC2), and enhances antiviral innate immunity by affecting interferon signaling. Clinically, reduced levels are associated with hepatocellular carcinoma development; conversely, it supports hepatitis C virus replication—making it both a biomarker and therapeutic target in these diseases. Circulating EV-incorporated miR‑122–5p also serves as a prognostic marker after cardiac interventions like TAVR. Therapeutic strategies targeting this molecule include antisense oligonucleotides such as miravirsen.

Other names

miR-122hsa-miR-122MIR122microRNA 122mir-122 microRNA precursor

Antisense inhibition of miR‑122 to reduce its activity and impact on viral replication or metabolic pathways