Reverse transcriptases lend a hand in splicing catalysis.
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ABSTRACT:
SUBMITTER: Piccirilli JA
PROVIDER: S-EPMC6548540 | biostudies-literature | 2016 Jun
REPOSITORIES: biostudies-literature
Publications
Reverse transcriptases lend a hand in splicing catalysis.
Piccirilli Joseph A JA Staley Jonathan P JP
Nature structural & molecular biology 20160601 6
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Project description: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.
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