mmu-miR-449a-5p agomir is a chemically modified miRNA analogue. It features full-chain methoxy modifications on the miRNA mature chain, with 2 thioate modifications at the 5' end and 4 at the 3' end, and is linked to a high-affinity cholesterol modification at the 3' end. miRNA agomirs can mimic endogenous miRNAs, enhancing miRNA activity. Compared to standard analogs, miRNA agomirs offer greater stability and inhibitory effects in animal experiments and more efficiently traverse cell membranes and interstitial spaces to accumulate in target cells.