MicroRNA

Small non-coding ribonucleic acid molecule

Micro ribonucleic acid (microRNA, miRNA, μRNA) are small, single-stranded, non-coding RNA molecules containing 21–23 nucleotides. Found in plants, animals, and even some viruses, microRNAs are involved in RNA silencing and post-transcriptional regulation of gene expression. miRNAs base-pair to complementary sequences in messenger RNA (mRNA) molecules, then silence these mRNA molecules by one or more of the following processes: Cleaving the mRNA strand into two pieces.

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