The group II intron maturase: a reverse transcriptase and splicing factor go hand in hand

Curr Opin Struct Biol. 2017 Dec:47:30-39. doi: 10.1016/ Epub 2017 May 18.


The splicing of group II introns in vivo requires the assistance of a multifunctional intron encoded protein (IEP, or maturase). Each IEP is also a reverse-transcriptase enzyme that enables group II introns to behave as mobile genetic elements. During splicing or retro-transposition, each group II intron forms a tight, specific complex with its own encoded IEP, resulting in a highly reactive holoenzyme. This review focuses on the structural basis for IEP function, as revealed by recent crystal structures of an IEP reverse transcriptase domain and cryo-EM structures of an IEP-intron complex. These structures explain how the same IEP scaffold is utilized for intron recognition, splicing and reverse transcription, while providing a physical basis for understanding the evolutionary transformation of the IEP into the eukaryotic splicing factor Prp8.

Publication types

  • Review

MeSH terms

  • Biological Evolution
  • Introns*
  • Models, Molecular
  • Nucleic Acid Conformation
  • Protein Binding
  • Protein Conformation
  • Protein Multimerization
  • RNA Splicing
  • RNA Splicing Factors / chemistry*
  • RNA Splicing Factors / metabolism*
  • RNA-Directed DNA Polymerase / chemistry*
  • RNA-Directed DNA Polymerase / metabolism*
  • Structure-Activity Relationship


  • RNA Splicing Factors
  • RNA-Directed DNA Polymerase