Identification of a novel component C2ORF3 in the lariat-intron complex: lack of C2ORF3 interferes with pre-mRNA splicing via intron turnover pathway

Genes Cells. 2014 Jan;19(1):78-87. doi: 10.1111/gtc.12114. Epub 2013 Dec 4.


To identify the novel factors involved in the postsplicing intron turnover pathway, we carried out immunoprecipitation with known postsplicing factors, hPrp43 and TFIP11. As an interacting factor, we identified C2ORF3 protein by mass spectrometry. We found that C2ORF3 protein is present in the previously characterized Intron Large (IL) complex with an excised lariat intron. In vitro splicing using C2ORF3-depleted nuclear extracts showed significant repression of splicing, suggesting that C2ORF3 protein is required for pre-mRNA splicing through its presumable role in efficient intron turnover. Interestingly, C2ORF3 protein is localized in both the nucleoplasm and nucleoli, which suggests a potential function in rRNA processing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • HEK293 Cells
  • HeLa Cells
  • Humans
  • Introns*
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • RNA Helicases / chemistry
  • RNA Helicases / genetics
  • RNA Helicases / metabolism
  • RNA Precursors / genetics
  • RNA Precursors / metabolism*
  • RNA Splicing
  • RNA Splicing Factors
  • Repressor Proteins / chemistry
  • Repressor Proteins / genetics*
  • Repressor Proteins / metabolism
  • Spliceosomes / genetics
  • Spliceosomes / metabolism


  • GCFC2 protein, human
  • Nuclear Proteins
  • RNA Precursors
  • RNA Splicing Factors
  • Repressor Proteins
  • TFIP11 protein, human
  • DHX15 protein, human
  • RNA Helicases