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MRNA 5'-leader trans-splicing in the chordates.

ABSTRACT: We report the discovery of mRNA 5'-leader trans-splicing (SL trans-splicing) in the chordates. In the ascidian protochordate Ciona intestinalis, the mRNAs of at least seven genes undergo trans-splicing of a 16-nucleotide 5'-leader apparently derived from a 46-nucleotide RNA that shares features with previously characterized splice donor SL RNAs. SL trans-splicing was known previously to occur in several protist and metazoan phyla, however, this is the first report of SL trans-splicing within the deuterostome division of the metazoa. SL trans-splicing is not known to occur in the vertebrates. However, because ascidians are primitive chordates related to vertebrate ancestors, our findings raise the possibility of ancestral SL trans-splicing in the vertebrate lineage.

SUBMITTER: Vandenberghe AE

PROVIDER: S-EPMC312621 | biostudies-literature | 2001 Feb

REPOSITORIES: biostudies-literature

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mRNA 5'-leader trans-splicing in the chordates.

Vandenberghe A E AE Meedel T H TH Hastings K E KE

Genes & development 20010201 3

We report the discovery of mRNA 5'-leader trans-splicing (SL trans-splicing) in the chordates. In the ascidian protochordate Ciona intestinalis, the mRNAs of at least seven genes undergo trans-splicing of a 16-nucleotide 5'-leader apparently derived from a 46-nucleotide RNA that shares features with previously characterized splice donor SL RNAs. SL trans-splicing was known previously to occur in several protist and metazoan phyla, however, this is the first report of SL trans-splicing within the ...[more]

PMID: 11159910

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