Display options
Share it on

Acta Neuropathol. 2021 Oct;142(4):609-627. doi: 10.1007/s00401-021-02340-0. Epub 2021 Jul 18.

HnRNP K mislocalisation is a novel protein pathology of frontotemporal lobar degeneration and ageing and leads to cryptic splicing.

Acta neuropathologica

Alexander Bampton, Ariana Gatt, Jack Humphrey, Sara Cappelli, Dipanjan Bhattacharya, Sandrine Foti, Anna-Leigh Brown, Yasmine Asi, Yi Hua Low, Marco Foiani, Towfique Raj, Emanuele Buratti, Pietro Fratta, Tammaryn Lashley

Affiliations

  1. The Queen Square Brain Bank for Neurological Disorders, Department of Clinical and Movement Neuroscience, UCL Queen Square Institute of Neurology, London, UK.
  2. Department of Neurodegenerative Diseases, UCL Queen Square Institute of Neurology, London, UK.
  3. Icahn School of Medicine at Mount Sinai, New York, NY, USA.
  4. International Centre for Genetic Engineering and Biotechnology (ICGEB), Padriciano 99, 34149, Trieste, Italy.
  5. The Firc Institute of Molecular Oncology Foundation (IFOM), Milan, Italy.
  6. Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK.
  7. Duke-NUS Medical School, Singapore, Singapore.
  8. University of Milan, Milan, Italy.
  9. Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK. [email protected].
  10. The Queen Square Brain Bank for Neurological Disorders, Department of Clinical and Movement Neuroscience, UCL Queen Square Institute of Neurology, London, UK. [email protected].
  11. Department of Neurodegenerative Diseases, UCL Queen Square Institute of Neurology, London, UK. [email protected].

PMID: 34274995 PMCID: PMC8423707 DOI: 10.1007/s00401-021-02340-0

Abstract

Heterogeneous nuclear ribonucleoproteins (HnRNPs) are a group of ubiquitously expressed RNA-binding proteins implicated in the regulation of all aspects of nucleic acid metabolism. HnRNP K is a member of this highly versatile hnRNP family. Pathological redistribution of hnRNP K to the cytoplasm has been linked to the pathogenesis of several malignancies but, until now, has been underexplored in the context of neurodegenerative disease. Here we show hnRNP K mislocalisation in pyramidal neurons of the frontal cortex to be a novel neuropathological feature that is associated with both frontotemporal lobar degeneration and ageing. HnRNP K mislocalisation is mutually exclusive to TDP-43 and tau pathological inclusions in neurons and was not observed to colocalise with mitochondrial, autophagosomal or stress granule markers. De-repression of cryptic exons in RNA targets following TDP-43 nuclear depletion is an emerging mechanism of potential neurotoxicity in frontotemporal lobar degeneration and the mechanistically overlapping disorder amyotrophic lateral sclerosis. We silenced hnRNP K in neuronal cells to identify the transcriptomic consequences of hnRNP K nuclear depletion. Intriguingly, by performing RNA-seq analysis we find that depletion of hnRNP K induces 101 novel cryptic exon events. We validated cryptic exon inclusion in an SH-SY5Y hnRNP K knockdown and in FTLD brain exhibiting hnRNP K nuclear depletion. We, therefore, present evidence for hnRNP K mislocalisation to be associated with FTLD and for this to induce widespread changes in splicing.

© 2021. The Author(s).

Keywords: Ageing; Cryptic exons; Frontotemporal dementia; Frontotemporal lobar degeneration; RNA; hnRNP K

References

  1. J Clin Invest. 2020 Nov 2;130(11):6080-6092 - PubMed
  2. Nucleic Acids Res. 2004 Jan 1;32(Database issue):D493-6 - PubMed
  3. EMBO J. 1997 Jun 16;16(12):3587-98 - PubMed
  4. EMBO J. 2018 Jun 1;37(11): - PubMed
  5. Nat Genet. 2018 Jan;50(1):151-158 - PubMed
  6. Development. 2011 Jul;138(14):3079-90 - PubMed
  7. Acta Neuropathol Commun. 2017 Apr 21;5(1):31 - PubMed
  8. Nat Neurosci. 2019 Feb;22(2):167-179 - PubMed
  9. Acta Neuropathol. 2017 Jul;134(1):65-78 - PubMed
  10. Nat Neurosci. 2018 Apr;21(4):552-563 - PubMed
  11. Nature. 2020 Jul;583(7818):711-719 - PubMed
  12. Nucleic Acids Res. 2017 Jul 27;45(13):8026-8045 - PubMed
  13. Acta Neuropathol. 2011 Jul;122(1):87-98 - PubMed
  14. J Neurosci. 2014 Jul 2;34(27):9088-95 - PubMed
  15. Bioinformatics. 2010 Sep 1;26(17):2204-7 - PubMed
  16. J Cell Mol Med. 2017 Jul;21(7):1266-1279 - PubMed
  17. Acta Neuropathol Commun. 2017 Jun 30;5(1):54 - PubMed
  18. Bioessays. 2004 Jun;26(6):629-38 - PubMed
  19. Brain. 2014 Jul;137(Pt 7):2040-51 - PubMed
  20. Nature. 2014 Mar 13;507(7491):195-200 - PubMed
  21. Nat Neurosci. 2019 Feb;22(2):180-190 - PubMed
  22. Hum Genet. 2016 Aug;135(8):851-67 - PubMed
  23. Neurodegener Dis Manag. 2014;4(6):439-54 - PubMed
  24. J Clin Pathol. 2019 Nov;72(11):725-735 - PubMed
  25. Hum Mol Genet. 2015 Mar 15;24(6):1655-69 - PubMed
  26. BMC Med Genomics. 2017 May 26;10(1):38 - PubMed
  27. J Neurochem. 2011 Oct;119(2):275-82 - PubMed
  28. Nucleic Acids Res. 2005 Oct 27;33(18):6000-10 - PubMed
  29. Acta Neuropathol Commun. 2019 Feb 12;7(1):18 - PubMed
  30. Neuropathol Appl Neurobiol. 2015 Dec;41(7):858-81 - PubMed
  31. Hum Mol Genet. 2012 Sep 15;21(18):4094-103 - PubMed
  32. Ther Adv Psychopharmacol. 2018 Jan;8(1):33-48 - PubMed
  33. Genome Biol. 2014;15(12):550 - PubMed
  34. Neuropathol Appl Neurobiol. 2019 Feb;45(1):6-18 - PubMed
  35. Bioinformatics. 2019 Jun 1;35(12):2084-2092 - PubMed
  36. RNA. 2018 Jun;24(6):761-768 - PubMed
  37. J Cell Biol. 2011 Mar 7;192(5):797-811 - PubMed
  38. Genes Cells. 2009 Feb;14(2):113-28 - PubMed
  39. Mol Cell Biol. 2003 Dec;23(23):8405-15 - PubMed
  40. J Biol Chem. 2008 Oct 24;283(43):28852-9 - PubMed
  41. Acta Neuropathol. 2020 Nov;140(5):599-623 - PubMed
  42. BMC Bioinformatics. 2011 Aug 04;12:323 - PubMed
  43. Mol Cell Biol. 1992 Jan;12(1):164-71 - PubMed
  44. Annu Rev Biochem. 1993;62:289-321 - PubMed
  45. Cell Death Dis. 2019 Oct 3;10(10):746 - PubMed
  46. PLoS One. 2012;7(8):e43120 - PubMed
  47. Hum Mol Genet. 2016 Dec 1;25(23):5083-5093 - PubMed
  48. Science. 2015 Aug 7;349(6248):650-5 - PubMed
  49. Int J Mol Sci. 2020 Nov 06;21(21): - PubMed
  50. Cell Rep. 2016 Sep 27;17(1):104-113 - PubMed
  51. Elife. 2016 Nov 18;5: - PubMed
  52. Bioinformatics. 2013 Jan 1;29(1):15-21 - PubMed
  53. FEBS Lett. 2004 Nov 5;577(1-2):134-40 - PubMed
  54. BMJ. 2013 Aug 06;347:f4827 - PubMed
  55. Genome Res. 2011 Oct;21(10):1572-82 - PubMed
  56. Nucleic Acids Res. 2019 Jan 8;47(D1):D766-D773 - PubMed
  57. Mol Cell Biol. 1988 May;8(5):2237-41 - PubMed
  58. Hum Mol Genet. 2017 May 1;26(9):1732-1746 - PubMed
  59. Cancer Lett. 2014 Oct 1;352(2):152-9 - PubMed
  60. Br J Cancer. 2006 Oct 9;95(7):921-7 - PubMed
  61. Nucleic Acids Res. 2020 Mar 18;48(5):2621-2642 - PubMed
  62. Nucleic Acids Res. 2020 Jul 9;48(12):6889-6905 - PubMed
  63. Cell. 2013 Jan 31;152(3):453-66 - PubMed
  64. Genome Res. 2010 Jan;20(1):110-21 - PubMed
  65. Acta Neuropathol. 2009 Nov;118(5):605-16 - PubMed
  66. Nucleic Acids Res. 2009 Jul;37(Web Server issue):W202-8 - PubMed
  67. J Alzheimers Dis. 2018;62(3):1467-1480 - PubMed

Publication Types

Grant support