A new function for nonsense-mediated mRNA-decay factors

Trends Genet. 2005 Mar;21(3):143-8. doi: 10.1016/j.tig.2005.01.007.


mRNAs often contain premature-termination (nonsense) codons as a result of mutations and RNA splicing errors. These nonsense codons cause rapid decay of the mRNAs that contain them, a phenomenon called nonsense-mediated mRNA decay (NMD). This response is thought to be a quality-control mechanism that protects cells from truncated dominant-negative proteins. Surprisingly, recent evidence strongly suggests that the NMD factors UPF1, UPF2, UPF3B, RNPS1, Y14 and MAGOH also promote translation of normal mRNAs in mammalian cells. This, along with an earlier discovery that NMD factors appear to dictate efficient translation termination, suggests that NMD factors do not merely function in RNA surveillance. These findings lead to the interesting question of why NMD factors evolved; are they for RNA-quality control or to promote efficient translation initiation and termination?

Publication types

  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Animals
  • CD55 Antigens / physiology*
  • Codon, Nonsense / physiology*
  • Humans
  • RNA, Messenger / genetics*
  • Ribonucleoproteins / physiology*


  • CD55 Antigens
  • Codon, Nonsense
  • RNA, Messenger
  • Ribonucleoproteins