Pentatricopeptide repeat proteins: a socket set for organelle gene expression

Trends Plant Sci. 2008 Dec;13(12):663-70. doi: 10.1016/j.tplants.2008.10.001. Epub 2008 Nov 12.


Pentatricopeptide repeat (PPR) proteins are RNA-binding proteins that are particularly prevalent in terrestrial plants. Although the PPR protein family was only recognized eight years ago, it is already clear that these proteins have a range of essential functions in post-transcriptional processes (including RNA editing, RNA splicing, RNA cleavage and translation) within mitochondria and chloroplasts. Several PPR proteins have been shown to act as fertility restorer genes in commercially important cytoplasmic male sterility systems. Here, we discuss several recent papers that cover their evolutionary history and molecular mode of action. We use these new data to propose hypotheses for their physiological roles that could explain why PPR proteins are so numerous in terrestrial plants.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Gene Expression Regulation, Plant
  • Mutation
  • Organelles / genetics
  • Organelles / metabolism
  • Plant Infertility
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Plants / genetics
  • Plants / metabolism*
  • RNA Processing, Post-Transcriptional*
  • RNA, Plant / metabolism
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / metabolism*


  • Plant Proteins
  • RNA, Plant
  • RNA-Binding Proteins