Spliced leader RNAs from lower eukaryotes are trans-spliced in mammalian cells.
Exon sequences present on separate RNA molecules can be joined by trans-splicing in trypanosomatids, Euglena, and in the nematode and trematode worms. Trans-splicing involves an interaction between a 5' splice site present in a spliced leader RNA and a 3' splice site located near the 5' end of pre-messenger RNAs. In vitro trans-splicing of artificial mammalian pre-mRNAs has been reported, but the efficiency of splicing appears to depend on sequence complementarity between the two substrates. There has been speculation that some natural pre-mRNAs can be trans-spliced in mammalian cells in vivo, but alternative interpretations have not been ruled out. Here we show that spliced leader RNAs can be accurately trans-spliced in mammalian cells in vivo and in vitro. Both nematode and mammalian 3' splice sites can function as acceptors for trans-splicing in vivo. These results reveal functional conservation in the splicing machinery between lower eukaryotes and mammals, and they directly demonstrate the potential for trans-splicing in mammalian cells.
Bruzik
J P
JP
Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, Massachusetts 02138.
Maniatis
T
T
D000199:Actins / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D017173:Caenorhabditis elegans / Q000235:genetics*; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D005091:Exons; D005822:Genetic Vectors; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D012326:RNA Splicing; D012333:RNA, Messenger / Q000235:genetics*; D012342:RNA, Small Nuclear / Q000235:genetics*; D015183:Restriction Mapping; D014162:Transfection; D014351:Trypanosomatina / Q000235:genetics*
D000199:Actins; D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D012342:RNA, Small Nuclear