Metazoan MicroRNAs

Cell. 2018 Mar 22;173(1):20-51. doi: 10.1016/j.cell.2018.03.006.


MicroRNAs (miRNAs) are ∼22 nt RNAs that direct posttranscriptional repression of mRNA targets in diverse eukaryotic lineages. In humans and other mammals, these small RNAs help sculpt the expression of most mRNAs. This article reviews advances in our understanding of the defining features of metazoan miRNAs and their biogenesis, genomics, and evolution. It then reviews how metazoan miRNAs are regulated, how they recognize and cause repression of their targets, and the biological functions of this repression, with a compilation of knockout phenotypes that shows that important biological functions have been identified for most of the broadly conserved miRNAs of mammals.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Base Pairing
  • Evolution, Molecular
  • Gene Expression Regulation
  • Gene Silencing
  • Genomics
  • Humans
  • MicroRNAs / antagonists & inhibitors
  • MicroRNAs / chemistry
  • MicroRNAs / metabolism*
  • Nucleic Acid Conformation
  • RNA Isoforms / genetics
  • RNA Isoforms / metabolism


  • MicroRNAs
  • RNA Isoforms