The nematode spliced leader RNA participates in trans-splicing as an Sm snRNP.

The nematode Caenorhabditis elegans has an unusual small nuclear RNA, containing a 100-nucleotide RNA molecule, spliced leader RNA, which donates its 5' 22 nucleotides to a variety of recipient RNAs by a trans-splicing reaction. The spliced leader RNA has a 5' trimethylguanosine (TMG) cap, which becomes the 5' end of trans-spliced mRNAs. We found that mature trans-spliced mRNAs were immunoprecipitable with anti-TMG cap antibodies and that TMG-containing dinucleotides specifically competed with the trans-spliced mRNAs for antibody binding. We also found that these mRNAs retained their TMG caps throughout development and that the TMG-capped mRNAs were polysome associated. Since the large majority of C. elegans mRNAs are not trans-spliced, the addition of the spliced leader and its TMG cap to a limited group of recipient RNAs may create a functionally distinct subset of mRNAs.

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Spliced-Leader RNA trans Splicing in a Chordate, Oikopleura dioica, with a Compact Genome

Molecular and Cellular Biology ◽

10.1128/mcb.24.17.7795-7805.2004 ◽

2004 ◽

Vol 24 (17) ◽

pp. 7795-7805 ◽

Cited By ~ 76

Author(s):

Philippe Ganot ◽

Torben Kallesøe ◽

Richard Reinhardt ◽

Daniel Chourrout ◽

Eric M. Thompson

Keyword(s):

Caenorhabditis Elegans ◽

Regulatory Elements ◽

Sm Proteins ◽

Oikopleura Dioica ◽

Spliced Leader ◽

Trans Splicing ◽

Spliced Leader Rna

ABSTRACT trans splicing of a spliced-leader RNA (SL RNA) to the 5′ ends of mRNAs has been shown to have a limited and sporadic distribution among eukaryotes. Within metazoans, only nematodes are known to process polycistronic pre-mRNAs, produced from operon units of transcription, into mature monocistronic mRNAs via an SL RNA trans-splicing mechanism. Here we demonstrate that a chordate with a highly compact genome, Oikopleura dioica, now joins Caenorhabditis elegans in coupling trans splicing with processing of polycistronic transcipts. We identified a single SL RNA which associates with Sm proteins and has a trimethyl guanosine cap structure reminiscent of spliceosomal snRNPs. The same SL RNA, estimated to be trans-spliced to at least 25% of O. dioica mRNAs, is used for the processing of both isolated or first cistrons and downstream cistrons in a polycistronic precursor. Remarkably, intercistronic regions in O. dioica are far more reduced than those in either nematodes or kinetoplastids, implying minimal cis-regulatory elements for coupling of 3′-end formation and trans splicing.

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Spliced Leader RNA-Mediated trans-Splicing in a Dinoflagellate, Karenia brevis

Journal of Eukaryotic Microbiology ◽

10.1111/j.1550-7408.2007.00282.x ◽

2007 ◽

Vol 54 (5) ◽

pp. 427-435 ◽

Cited By ~ 72

Author(s):

KRISTY B. LIDIE ◽

FRANCES M. VAN DOLAH

Keyword(s):

Karenia Brevis ◽

Spliced Leader ◽

Trans Splicing ◽

Spliced Leader Rna

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The evolution of spliced leader trans-splicing in nematodes

Biochemical Society Transactions ◽

10.1042/bst0381125 ◽

2010 ◽

Vol 38 (4) ◽

pp. 1125-1130 ◽

Cited By ~ 10

Author(s):

Jonathan Pettitt ◽

Neale Harrison ◽

Ian Stansfield ◽

Bernadette Connolly ◽

Berndt Müller

Keyword(s):

Caenorhabditis Elegans ◽

Common Ancestor ◽

Model Organism ◽

Spliced Leader ◽

Trans Splicing ◽

Rna Genes ◽

Spliced Leader Rna

Spliced leader trans-splicing occurs in many primitive eukaryotes including nematodes. Most of our knowledge of trans-splicing in nematodes stems from the model organism Caenorhabditis elegans and relatives, and from work with Ascaris. Our investigation of spliced leader trans-splicing in distantly related Dorylaimia nematodes indicates that spliced-leader trans-splicing arose before the nematode phylum and suggests that the spliced leader RNA gene complements in extant nematodes have evolved from a common ancestor with a diverse set of spliced leader RNA genes.

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