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bioRxiv · 10.1101/2025.02.14.638102

An RNA Splicing System that Excises Transposons from Animal mRNAs

Zhao, L.-W.·Nardone, C.·Paulo, J. A.·Elledge, S.·Kennedy, S.
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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.

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Zhao, L.-W., Nardone, C., Paulo, J. A., Elledge, S., Kennedy, S.. 2025-02-17. An RNA Splicing System that Excises Transposons from Animal mRNAs. https://doi.org/10.1101/2025.02.14.638102

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