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Rare Dis. 2013 Jun 06;1:e25230. doi: 10.4161/rdis.25230. eCollection 2013.

Senataxin protects the genome: Implications for neurodegeneration and other abnormalities.

Rare diseases (Austin, Tex.)

Martin F Lavin, Abrey J Yeo, Olivier J Becherel

Affiliations

  1. Queensland Institute of Medical Research; Radiation Biology and Oncology; Brisbane, QLD, Australia ; University of Queensland Centre for Clinical Research; Herston, QLD, Australia.
  2. Queensland Institute of Medical Research; Radiation Biology and Oncology; Brisbane, QLD, Australia ; School of Medicine; University of Queensland; Herston, QLD, Australia.
  3. Queensland Institute of Medical Research; Radiation Biology and Oncology; Brisbane, QLD, Australia ; School of Chemistry & Molecular Biosciences; University of Queensland; St. Lucia, QLD, Australia.

PMID: 25003001 PMCID: PMC3927485 DOI: 10.4161/rdis.25230

Abstract

Ataxia oculomotor apraxia type 2 (AOA2) is a rare autosomal recessive disorder characterized by cerebellar atrophy, peripheral neuropathy, loss of Purkinje cells and elevated α-fetoprotein. AOA2 is caused by mutations in the SETX gene that codes for the high molecular weight protein senataxin. Mutations in this gene also cause dominant neurodegenerative disorders. Similar to that observed for other autosomal recessive ataxias, this protein protects the integrity of the genome against oxidative and other forms of DNA damage to reduce the risk of neurodegeneration. Senataxin functions in transcription termination and RNA splicing and it has been shown to resolve RNA/DNA hybrids (R-loops) that arise at transcription pause sites or when transcription is blocked. Recent data suggest that this protein functions at the interface between transcription and DNA replication to minimise the risk of collision and maintain genome stability. Our recent data using SETX gene-disrupted mice revealed that male mice were defective in spermatogenesis and were infertile. DNA double strand-breaks persisted throughout meiosis and crossing-over failed in SETX mutant mice. These changes can be explained by the accumulation of R-loops, which interfere with Holiday junctions and crossing-over. We also showed that senataxin was localized to the XY body in pachytene cells and was involved in transcriptional silencing of these chromosomes. While the defect in meiotic recombination was striking in these animals, there was no evidence of neurodegeneration as observed in AOA2 patients. We discuss here potentially different roles for senataxin in proliferating and post-mitotic cells.

Keywords: Ataxia oculomotor apraxia type 2 (AOA2); DNA double strand breaks; R-loops; RNA processing; SETX gene; neurodegeneration; senataxin

References

  1. Eur J Hum Genet. 2012 Jun;20(6): - PubMed
  2. FEBS J. 2011 Oct;278(19):3550-68 - PubMed
  3. Brain. 2009 Oct;132(Pt 10):2688-98 - PubMed
  4. Nucleic Acids Res. 1997 Dec 1;25(23):4778-85 - PubMed
  5. Mol Cell. 2011 Jun 24;42(6):794-805 - PubMed
  6. Am J Hum Genet. 2004 Jun;74(6):1128-35 - PubMed
  7. Nucleic Acids Res. 2004 Apr 30;32(8):2441-52 - PubMed
  8. J Cell Biol. 2007 Jun 18;177(6):969-79 - PubMed
  9. Cerebellum. 2009 Dec;8(4):448-53 - PubMed
  10. DNA Repair (Amst). 2011 Feb 7;10(2):199-209 - PubMed
  11. FEBS J. 2011 Oct;278(19):3569-77 - PubMed
  12. Cell. 2012 Nov 9;151(4):835-846 - PubMed
  13. Hum Mol Genet. 2009 Sep 15;18(18):3384-96 - PubMed
  14. Cell. 2005 Aug 12;122(3):365-78 - PubMed
  15. Nucleic Acids Res. 2012 Jan;40(2):e16 - PubMed
  16. Mol Cell. 2012 Mar 30;45(6):814-25 - PubMed
  17. Orphanet J Rare Dis. 2006 Nov 17;1:47 - PubMed
  18. Lancet Neurol. 2007 Mar;6(3):245-57 - PubMed
  19. Neurogenetics. 2007 Jan;8(1):45-9 - PubMed
  20. Nat Rev Genet. 2008 Mar;9(3):204-17 - PubMed
  21. Neurobiol Dis. 2006 Jul;23(1):97-108 - PubMed
  22. Nat Genet. 2004 Mar;36(3):225-7 - PubMed
  23. Neurology. 2006 Apr 25;66(8):1207-10 - PubMed
  24. DNA Repair (Amst). 2013 Aug;12(8):612-9 - PubMed
  25. Mol Cell Biol. 2013 Jan;33(2):406-17 - PubMed
  26. EMBO Mol Med. 2013 Feb;5(2):221-34 - PubMed
  27. Mol Cell. 2013 Jan 10;49(1):55-66 - PubMed
  28. Mol Cell. 2011 Jan 7;41(1):21-32 - PubMed
  29. PLoS Genet. 2013 Apr;9(4):e1003435 - PubMed
  30. Am J Med Genet A. 2007 Aug 1;143A(15):1775-7 - PubMed
  31. Brain. 2004 Apr;127(Pt 4):759-67 - PubMed
  32. Brain. 2011 Jun;134(Pt 6):1808-28 - PubMed

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