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.
© 2013 The Authors Genes to Cells © 2013 by the Molecular Biology Society of Japan and Wiley Publishing Asia Pty Ltd.