Human micro RNAs

Abstract

MicroRNAs (miRNAs) are a diverse class of 20–22 nucleotide small RNAs that regulate translation of a wide range of genes by complementary binding to untranslated regions of mRNA targets. Over 1300 miRNA sequences have been identified from animals and plants, with over 200 genes in the human genome. miRNAs appear to be expressed from a variety of genomic contexts including from autonomous promoters, as polycistronic transcripts, and processed from introns of protein‐coding genes.