Splicing factors Sf3A2 and Prp31 have direct roles in mitotic chromosome segregation
- University of Rome, Italy
- University of Exeter, United Kingdom
Abstract
Several studies have shown that RNAi-mediated depletion of splicing factors (SFs) results in mitotic abnormalities. However, it is currently unclear whether these abnormalities reflect defective splicing of specific pre-mRNAs or a direct role of the SFs in mitosis. Here we show that two highly conserved SFs, Sf3A2 and Prp31, are required for chromosome segregation in both Drosophila and human cells. Injections of anti-Sf3A2 and anti-Prp31 antibodies into Drosophila embryos disrupt mitotic division within 1 minute, arguing strongly against a splicing-related mitotic function of these factors. We demonstrate that both SFs bind spindle microtubules (MTs) and the Ndc80 complex, which in Sf3A2- and Prp31-depleted cells is not tightly associated with the kinetochores; in HeLa cells the Ndc80/HEC1-SF interaction is restricted to the M phase. These results indicate that Sf3A2 and Prp31 directly regulate interactions among kinetochores, spindle microtubules and the Ndc80 complex in both Drosophila and human cells.
Data availability
All data generated or analyzed during this study are included in the manuscript and Supplementary File 1. The full dataset for proteomic analyses reported in Figures 6 and Supplementary File 1 can be found at https://www.thewakefieldlab.com/ms; the significantly reduced protein IDs for each RNAi experiment were interrogated using a Gene Ontology (GO) classifier (GOTermMapper (https://go.princeton.edu/cgi-bin/GOTermMapper), concentrating on the GO terms ""cell division"" (GO:0051301), ""mitotic cell cycle"" (GO:0000278) and ""chromosome segregation"" (GO:0007059). Source data files have been provided for Figures 1, 4, 5, 7, 8, and 9.
Article and author information
Author details
Funding
Associazione Italiana per la Ricerca sul Cancro (IG16020)
- Maurizio Gatti
Ministero dell'Istruzione, dell'Università e della Ricerca
- Silvia Bonaccorsi
Biotechnology and Biological Sciences Research Council (BB/K017837/1)
- James G Wakefield
Associazione Italiana per la Ricerca sul Cancro (IG20528)
- Maurizio Gatti
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Pellacani et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Splicing factors Sf3A2 and Prp31 have direct roles in mitotic chromosome segregation
eLife 7:e40325.
https://doi.org/10.7554/eLife.40325
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