Mitochondrial poly(A) polymerase and polyadenylation

Biochim Biophys Acta. 2012 Sep-Oct;1819(9-10):992-7. doi: 10.1016/j.bbagrm.2011.10.012. Epub 2011 Dec 7.


Polyadenylation of mitochondrial RNAs in higher eukaryotic organisms have diverse effects on their function and metabolism. Polyadenylation completes the UAA stop codon of a majority of mitochondrial mRNAs in mammals, regulates the translation of the mRNAs, and has diverse effects on their stability. In contrast, polyadenylation of most mitochondrial mRNAs in plants leads to their degradation, consistent with the bacterial origin of this organelle. PAPD1 (mtPAP, TUTase1), a noncanonical poly(A) polymerase (ncPAP), is responsible for producing the poly(A) tails in mammalian mitochondria. The crystal structure of human PAPD1 was reported recently, offering molecular insights into its catalysis. This article is part of a Special Issue entitled: Mitochondrial Gene Expression.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Animals
  • DNA-Directed RNA Polymerases* / chemistry
  • DNA-Directed RNA Polymerases* / genetics
  • DNA-Directed RNA Polymerases* / metabolism
  • Humans
  • Mitochondria* / genetics
  • Mitochondria* / metabolism
  • Mitochondrial Proteins* / chemistry
  • Mitochondrial Proteins* / genetics
  • Mitochondrial Proteins* / metabolism
  • Plants / genetics
  • Polyadenylation / genetics*
  • Protein Conformation
  • RNA Stability / genetics
  • RNA, Messenger* / genetics
  • RNA, Messenger* / metabolism
  • RNA, Mitochondrial
  • Yeasts / genetics


  • Mitochondrial Proteins
  • RNA, Messenger
  • RNA, Mitochondrial
  • mitochondrial messenger RNA
  • DNA-Directed RNA Polymerases
  • MTPAP protein, human