An RNA Splicing System that Excises Transposons from Animal mRNAs
Listed in
This article is not in any list yet, why not save it to one of your lists.Abstract
All genomes harbor mobile genetic parasites called transposable elements (TEs). Here we describe a system, which we term SOS splicing, that protects C. elegans and human genes from DNA transposon-mediated disruption by excising these TEs from host mRNAs. SOS splicing, which operates independently of the spliceosome, is a pattern recognition system triggered by base-pairing of inverted terminal repeat elements, which are a defining feature of the DNA transposons. We identify three factors required for SOS splicing in both C. elegans and human cells; AKAP17A, which binds TE-containing mRNAs; the RNA ligase RTCB; and CAAP1, which bridges RTCB and AKAP17A, allowing RTCB to ligate mRNA fragments generated by TE excision. We propose that SOS splicing is a novel, conserved, and RNA structure-directed mode of mRNA splicing and that one function of SOS splicing is to genetically buffer animals from the deleterious effects of TE-mediated gene perturbation.
