Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Hyperactivation of HUSH complex function by Charcot–Marie–Tooth disease mutation in MORC2

Abstract

Dominant mutations in the MORC2 gene have recently been shown to cause axonal Charcot–Marie–Tooth (CMT) disease, but the cellular function of MORC2 is poorly understood. Here, through a genome-wide CRISPR–Cas9-mediated forward genetic screen, we identified MORC2 as an essential gene required for epigenetic silencing by the HUSH complex. HUSH recruits MORC2 to target sites in heterochromatin. We exploited a new method, differential viral accessibility (DIVA), to show that loss of MORC2 results in chromatin decompaction at these target loci, which is concomitant with a loss of H3K9me3 deposition and transcriptional derepression. The ATPase activity of MORC2 is critical for HUSH-mediated silencing, and the most common alteration affecting the ATPase domain in CMT patients (p.Arg252Trp) hyperactivates HUSH-mediated repression in neuronal cells. These data define a critical role for MORC2 in epigenetic silencing by the HUSH complex and provide a mechanistic basis underpinning the role of MORC2 mutations in CMT disease.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: A genome-wide CRISPR–Cas9-mediated forward genetic screen identifies an essential role for MORC2 in transgene silencing by the HUSH complex.
Figure 2: The ATPase, CW and coiled-coil domains of MORC2 are required for HUSH complex function.
Figure 3: The HUSH complex recruits MORC2 to heterochromatic target sites.
Figure 4: Loss of MORC2 results in chromatin decompaction at HUSH-target sites.
Figure 5: Chromatin decompaction in MORC2-knockout cells is accompanied by a loss of H3K9me3 and transcriptional depression.
Figure 6: The p.Arg252Trp alteration in MORC2, which is associated with CMT disease, hyperactivates HUSH-mediated epigenetic repression.

Similar content being viewed by others

Accession codes

Primary accessions

Gene Expression Omnibus

References

  1. Wang, J., Lawry, S.T., Cohen, A.L. & Jia, S. Chromosome boundary elements and regulation of heterochromatin spreading. Cell. Mol. Life Sci. 71, 4841–4852 (2014).

    Article  CAS  Google Scholar 

  2. Margueron, R. & Reinberg, D. The Polycomb complex PRC2 and its mark in life. Nature 469, 343–349 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  3. Becker, J.S., Nicetto, D. & Zaret, K.S. H3K9me3-dependent heterochromatin: barrier to cell fate changes. Trends Genet. 32, 29–41 (2016).

    Article  CAS  Google Scholar 

  4. Talbert, P.B. & Henikoff, S. Spreading of silent chromatin: inaction at a distance. Nat. Rev. Genet. 7, 793–803 (2006).

    Article  CAS  Google Scholar 

  5. Schotta, G., Ebert, A., Dorn, R. & Reuter, G. Position-effect variegation and the genetic dissection of chromatin regulation in Drosophila. Semin. Cell Dev. Biol. 14, 67–75 (2003).

    Article  CAS  Google Scholar 

  6. Akhtar, W. et al. Chromatin position effects assayed by thousands of reporters integrated in parallel. Cell 154, 914–927 (2013).

    Article  CAS  Google Scholar 

  7. Kotecki, M., Reddy, P.S. & Cochran, B.H. Isolation and characterization of a near-haploid human cell line. Exp. Cell Res. 252, 273–280 (1999).

    Article  CAS  Google Scholar 

  8. Carette, J.E. et al. Haploid genetic screens in human cells identify host factors used by pathogens. Science 326, 1231–1235 (2009).

    Article  CAS  Google Scholar 

  9. Tchasovnikarova, I.A. et al. Epigenetic silencing by the HUSH complex mediates position-effect variegation in human cells. Science 348, 1481–1485 (2015).

    Article  CAS  Google Scholar 

  10. Schultz, D.C., Ayyanathan, K., Negorev, D., Maul, G.G. & Rauscher, F.J. III. SETDB1: a novel KAP-1-associated histone H3, lysine 9-specific methyltransferase that contributes to HP1-mediated silencing of euchromatic genes by KRAB zinc-finger proteins. Genes Dev. 16, 919–932 (2002).

    Article  CAS  Google Scholar 

  11. Kokura, K., Sun, L., Bedford, M.T. & Fang, J. Methyl-H3K9-binding protein MPP8 mediates E-cadherin gene silencing and promotes tumour cell motility and invasion. EMBO J. 29, 3673–3687 (2010).

    Article  CAS  Google Scholar 

  12. Harten, S.K. et al. The first mouse mutants of D14Abb1e (Fam208a) show that it is critical for early development. Mamm. Genome 25, 293–303 (2014).

    Article  CAS  Google Scholar 

  13. Soehn, A.S. et al. Periphilin is strongly expressed in the murine nervous system and is indispensable for murine development. Genesis 47, 697–707 (2009).

    Article  CAS  Google Scholar 

  14. Timms, R.T. et al. Genetic dissection of mammalian ERAD through comparative haploid and CRISPR forward genetic screens. Nat. Commun. 7, 11786 (2016).

    Article  CAS  Google Scholar 

  15. Timms, R.T., Tchasovnikarova, I.A., Antrobus, R., Dougan, G. & Lehner, P.J. ATF7IP-mediated stabilization of the histone methyltransferase setdb1 is essential for heterochromatin formation by the HUSH complex. Cell Rep. 17, 653–659 (2016).

    Article  CAS  Google Scholar 

  16. Wang, T., Wei, J.J., Sabatini, D.M. & Lander, E.S. Genetic screens in human cells using the CRISPR-Cas9 system. Science 343, 80–84 (2014).

    Article  CAS  Google Scholar 

  17. Shalem, O. et al. Genome-scale CRISPR-Cas9 knockout screening in human cells. Science 343, 84–87 (2014).

    Article  CAS  Google Scholar 

  18. Sanjana, N.E., Shalem, O. & Zhang, F. Improved vectors and genome-wide libraries for CRISPR screening. Nat. Methods 11, 783–784 (2014).

    Article  CAS  Google Scholar 

  19. Li, D.-Q., Nair, S.S. & Kumar, R. The MORC family: new epigenetic regulators of transcription and DNA damage response. Epigenetics 8, 685–693 (2013).

    Article  CAS  Google Scholar 

  20. Moissiard, G. et al. MORC family ATPases required for heterochromatin condensation and gene silencing. Science 336, 1448–1451 (2012).

    Article  CAS  Google Scholar 

  21. Pastor, W.A. et al. MORC1 represses transposable elements in the mouse male germline. Nat. Commun. 5, 5795 (2014).

    Article  CAS  Google Scholar 

  22. Liu, Y. et al. Family-wide characterization of histone binding abilities of human CW domain-containing proteins. J. Biol. Chem. 291, 9000–9013 (2016).

    Article  CAS  Google Scholar 

  23. Liu, Y. et al. Structure and function of CW domain containing proteins. Curr. Protein Pept. Sci. 17, 497–506 (2016).

    Article  CAS  Google Scholar 

  24. Li, S. et al. Mouse MORC3 is a GHKL ATPase that localizes to H3K4me3 marked chromatin. Proc. Natl. Acad. Sci. USA 113, E5108–E5116 (2016).

    Article  CAS  Google Scholar 

  25. Li, D.-Q. et al. MORC2 signaling integrates phosphorylation-dependent, ATPase-coupled chromatin remodeling during the DNA damage response. Cell Rep. 2, 1657–1669 (2012).

    Article  CAS  Google Scholar 

  26. Buenrostro, J.D., Giresi, P.G., Zaba, L.C., Chang, H.Y. & Greenleaf, W.J. Transposition of native chromatin for fast and sensitive epigenomic profiling of open chromatin, DNA-binding proteins and nucleosome position. Nat. Methods 10, 1213–1218 (2013).

    Article  CAS  Google Scholar 

  27. Wu, J. et al. The landscape of accessible chromatin in mammalian preimplantation embryos. Nature 534, 652–657 (2016).

    Article  CAS  Google Scholar 

  28. Kvaratskhelia, M., Sharma, A., Larue, R.C., Serrao, E. & Engelman, A. Molecular mechanisms of retroviral integration site selection. Nucleic Acids Res. 42, 10209–10225 (2014).

    Article  CAS  Google Scholar 

  29. Sevilla, T. et al. Mutations in the MORC2 gene cause axonal Charcot-Marie-Tooth disease. Brain 139, 62–72 (2016).

    Article  Google Scholar 

  30. Albulym, O.M. et al. MORC2 mutations cause axonal Charcot-Marie-Tooth disease with pyramidal signs. Ann. Neurol. 79, 419–427 (2016).

    Article  CAS  Google Scholar 

  31. Laššuthová, P. et al. Severe axonal Charcot-Marie-Tooth disease with proximal weakness caused by de novo mutation in the MORC2 gene. Brain 139, e26 (2016).

    Article  Google Scholar 

  32. Hyun, Y.S., Hong, Y.B., Choi, B.O. & Chung, K.W. Clinico-genetics in Korean Charcot-Marie-Tooth disease type 2Z with MORC2 mutations. Brain 139, e40 (2016).

    Article  Google Scholar 

  33. Zhao, X. et al. MORC2 mutations in a cohort of Chinese patients with Charcot-Marie-Tooth disease type 2. Brain 139, e56 (2016).

    Article  Google Scholar 

  34. Wang, T. et al. Identification and characterization of essential genes in the human genome. Science 350, 1096–101 (2015).

    Article  CAS  Google Scholar 

  35. Doench, J.G. et al. Optimized sgRNA design to maximize activity and minimize off-target effects of CRISPR-Cas9. Nat. Biotechnol. 34, 184–191 (2016).

    Article  CAS  Google Scholar 

  36. Horlbeck, M.A. et al. Compact and highly active next-generation libraries for CRISPR-mediated gene repression and activation. eLife 5, e19760 (2016).

    Article  Google Scholar 

  37. Francis, N.J., Kingston, R.E. & Woodcock, C.L. Chromatin compaction by a polycomb group protein complex. Science 306, 1574–1577 (2004).

    Article  CAS  Google Scholar 

  38. Grau, D.J. et al. Compaction of chromatin by diverse Polycomb group proteins requires localized regions of high charge. Genes Dev. 25, 2210–2221 (2011).

    Article  CAS  Google Scholar 

  39. Clapier, C.R. & Cairns, B.R. The biology of chromatin remodeling complexes. Annu. Rev. Biochem. 78, 273–304 (2009).

    Article  CAS  Google Scholar 

  40. Zhang, Y., LeRoy, G., Seelig, H.P., Lane, W.S. & Reinberg, D. The dermatomyositis-specific autoantigen Mi2 is a component of a complex containing histone deacetylase and nucleosome remodeling activities. Cell 95, 279–289 (1998).

    Article  CAS  Google Scholar 

  41. Schottmann, G., Wagner, C., Seifert, F., Stenzel, W. & Schuelke, M. MORC2 mutation causes severe spinal muscular atrophy-phenotype, cerebellar atrophy, and diaphragmatic paralysis. Brain 139, e70 (2016).

    Article  Google Scholar 

  42. Stebbins, C.E. et al. Crystal structure of an Hsp90-geldanamycin complex: targeting of a protein chaperone by an antitumor agent. Cell 89, 239–250 (1997).

    Article  CAS  Google Scholar 

  43. Sharma, S.V., Agatsuma, T. & Nakano, H. Targeting of the protein chaperone, HSP90, by the transformation suppressing agent, radicicol. Oncogene 16, 2639–2645 (1998).

    Article  CAS  Google Scholar 

  44. Chen, K. et al. Genome-wide binding and mechanistic analyses of Smchd1-mediated epigenetic regulation. Proc. Natl. Acad. Sci. USA 112, E3535–E3544 (2015).

    Article  CAS  Google Scholar 

  45. Ran, F.A. et al. Genome engineering using the CRISPR-Cas9 system. Nat. Protoc. 8, 2281–2308 (2013).

    Article  CAS  Google Scholar 

  46. Koike-Yusa, H., Li, Y., Tan, E.-P., Velasco-Herrera, Mdel.C. & Yusa, K. Genome-wide recessive genetic screening in mammalian cells with a lentiviral CRISPR-guide RNA library. Nat. Biotechnol. 32, 267–273 (2014).

    Article  CAS  Google Scholar 

  47. Lerdrup, M., Johansen, J.V., Agrawal-Singh, S. & Hansen, K. An interactive environment for agile analysis and visualization of ChIP-sequencing data. Nat. Struct. Mol. Biol. 23, 349–357 (2016).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We are indebted to CIMR core facilities: R. Schulte and his team for FACS, and M. Gratian and M. Bowen for microscopy. We thank S. Andrews for assistance with data analysis with SeqMonk, and S. Kundu and M. Tolstorukov for helpful discussions. We thank B. Cochran (Tufts University), F. Randow (MRC-LMB), D. Rubinsztein (CIMR) and M. Brenner (Harvard Medical School) for providing materials. This work was supported by the Wellcome Trust, through a Principal Research Fellowship to P.J.L. (101835/Z/13/Z), a Senior Research Fellowship to Y.M. (101908/Z/13/Z), a Sir Henry Wellcome Postdoctoral Fellowship to R.T.T. (201387/Z/16/Z) and a PhD studentship to I.A.T., and by the BBSRC, through a Future Leader Fellowship to C.H.D. I.A.T. is supported as a Damon Runyon Fellow by the Damon Runyon Cancer Research Foundation (DRG-2277-16). The CIMR is in receipt of a Wellcome Trust strategic award.

Author information

Authors and Affiliations

Authors

Contributions

I.A.T., R.T.T. and P.J.L. conceived the study. Except for the in vitro expression and purification experiments, which were carried out by C.H.D., I.A.T. and R.T.T. performed all of the experiments and, together with Y.M. and P.J.L., analyzed the data and wrote the manuscript. G.D., R.C.R. and R.E.K. contributed essential reagents.

Corresponding author

Correspondence to Paul J Lehner.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Text and Figures

Supplementary Figures 1–10. (PDF 2738 kb)

Supplementary Table 1

Composition of MORC2 mutants. (XLSX 10 kb)

Supplementary Table 2

Full DIVA data quantifying viral accessibility across all genomic loci in wild-type versus MORC2 knockout HeLa cells. (XLSX 24640 kb)

Supplementary Table 3

Oligonucleotide sequences. (XLSX 11 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Tchasovnikarova, I., Timms, R., Douse, C. et al. Hyperactivation of HUSH complex function by Charcot–Marie–Tooth disease mutation in MORC2. Nat Genet 49, 1035–1044 (2017). https://doi.org/10.1038/ng.3878

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ng.3878

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing