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

ABSTRACT: 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.

SUBMITTER: Zhao C

PROVIDER: S-EPMC5694389 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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

Zhao Chen C Pyle Anna Marie AM

Current opinion in structural biology 20170518

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 s ...[more]

PMID: 28528306

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2019-11-11 | GSE138200 | GEO

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