Numerous recursive sites contribute to accuracy of splicing in long introns in flies

PLoS Genet. 2018 Aug 27;14(8):e1007588. doi: 10.1371/journal.pgen.1007588. eCollection 2018 Aug.

Abstract

Recursive splicing, a process by which a single intron is removed from pre-mRNA transcripts in multiple distinct segments, has been observed in a small subset of Drosophila melanogaster introns. However, detection of recursive splicing requires observation of splicing intermediates that are inherently unstable, making it difficult to study. Here we developed new computational approaches to identify recursively spliced introns and applied them, in combination with existing methods, to nascent RNA sequencing data from Drosophila S2 cells. These approaches identified hundreds of novel sites of recursive splicing, expanding the catalog of recursively spliced fly introns by 4-fold. A subset of recursive sites were validated by RT-PCR and sequencing. Recursive sites occur in most very long (> 40 kb) fly introns, including many genes involved in morphogenesis and development, and tend to occur near the midpoints of introns. Suggesting a possible function for recursive splicing, we observe that fly introns with recursive sites are spliced more accurately than comparably sized non-recursive introns.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Drosophila melanogaster / genetics*
  • Gene Ontology
  • Introns*
  • Models, Theoretical
  • RNA Precursors / genetics
  • RNA Splice Sites
  • RNA Splicing*
  • RNA, Messenger / genetics
  • Reproducibility of Results
  • Sequence Analysis, RNA
  • Transcription, Genetic

Substances

  • RNA Precursors
  • RNA Splice Sites
  • RNA, Messenger