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An organellar maturase associates with multiple group II introns.

ABSTRACT: Bacterial group II introns encode maturase proteins required for splicing. In organelles of photosynthetic land plants, most of the group II introns have lost the reading frames for maturases. Here, we show that the plastidial maturase MatK not only interacts with its encoding intron within trnK-UUU, but also with six additional group II introns, all belonging to intron subclass IIA. Mapping analyses of RNA binding sites revealed MatK to recognize multiple regions within the trnK intron. Organellar group II introns are considered to be the ancestors of nuclear spliceosomal introns. That MatK associates with multiple intron ligands makes it an attractive model for an early trans-acting nuclear splicing activity.

SUBMITTER: Zoschke R

PROVIDER: S-EPMC2840290 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature

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An organellar maturase associates with multiple group II introns.

Zoschke Reimo R Nakamura Masayuki M Liere Karsten K Sugiura Masahiro M Börner Thomas T Schmitz-Linneweber Christian C

Proceedings of the National Academy of Sciences of the United States of America 20100128 7

Bacterial group II introns encode maturase proteins required for splicing. In organelles of photosynthetic land plants, most of the group II introns have lost the reading frames for maturases. Here, we show that the plastidial maturase MatK not only interacts with its encoding intron within trnK-UUU, but also with six additional group II introns, all belonging to intron subclass IIA. Mapping analyses of RNA binding sites revealed MatK to recognize multiple regions within the trnK intron. Organel ...[more]

PMID: 20133623

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