The preRC protein ORCA organizes heterochromatin by assembling histone H3 lysine 9 methyltransferases on chromatin

  1. Sumanprava Giri
  2. Vasudha Aggarwal
  3. Julien Pontis
  4. Zhen Shen
  5. Arindam Chakraborty
  6. Abid Khan
  7. Craig Mizzen
  8. Kannanganattu V Prasanth
  9. Slimane Ait-Si-Ali
  10. Taekjip Ha
  11. Supriya G Prasanth  Is a corresponding author
  1. University of Illinois at Urbana-Champaign, United States
  2. Centre National de la Recherche Scientifique, France

Abstract

Heterochromatic domains are enriched with repressive histone marks, including histone H3 lysine 9 methylation, written by lysine methyltransferases (KMTs). The pre-replication complex protein Origin Recognition Complex-Associated (ORCA/LRWD1) preferentially localizes to heterochromatic regions in post-replicated cells. Its role in heterochromatin organization remained elusive. ORCA recognizes methylated H3K9 marks and interacts with repressive KMTs, including G9a/GLP and Suv39H1 in a chromatin context-dependent manner. Single-molecule pull-down assays demonstrate that ORCA-ORC and multiple H3K9 KMTs exist in a single complex and that ORCA stabilizes H3K9 KMT complex. Cells lacking ORCA show alterations in chromatin architecture, with significantly reduced H3K9 di- and tri-methylation at specific chromatin sites. Changes in heterochromatin structure due to loss of ORCA affects replication timing, preferentially at the late-replicating regions. We demonstrate that ORCA acts as a scaffold for the establishment of H3K9 KMT complex and its association and activity at specific chromatin sites is crucial for the organization of heterochromatin structure.

Article and author information

Author details

  1. Sumanprava Giri

    Department of Cell and Developmental Biology,, University of Illinois at Urbana-Champaign, Champaign, United States
    Competing interests
    No competing interests declared.
  2. Vasudha Aggarwal

    Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, Champaign, United States
    Competing interests
    No competing interests declared.
  3. Julien Pontis

    Université Paris Diderot, Sorbonne Paris Cité, Laboratoire Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique, Paris, France
    Competing interests
    No competing interests declared.
  4. Zhen Shen

    Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Champaign, United States
    Competing interests
    No competing interests declared.
  5. Arindam Chakraborty

    Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Champaign, United States
    Competing interests
    No competing interests declared.
  6. Abid Khan

    Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Champaign, United States
    Competing interests
    No competing interests declared.
  7. Craig Mizzen

    Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Champaign, United States
    Competing interests
    No competing interests declared.
  8. Kannanganattu V Prasanth

    Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Champaign, United States
    Competing interests
    No competing interests declared.
  9. Slimane Ait-Si-Ali

    Université Paris Diderot, Sorbonne Paris Cité, Laboratoire Epigénétique et Destin Cellulaire, UMR7216, Centre National de la Recherche Scientifique, Paris, France
    Competing interests
    No competing interests declared.
  10. Taekjip Ha

    Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, Champaign, United States
    Competing interests
    Taekjip Ha, Reviewing editor, eLife.
  11. Supriya G Prasanth

    Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, Champaign, United States
    For correspondence
    supriyap@life.illinois.edu
    Competing interests
    No competing interests declared.

Copyright

© 2015, Giri 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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  1. Sumanprava Giri
  2. Vasudha Aggarwal
  3. Julien Pontis
  4. Zhen Shen
  5. Arindam Chakraborty
  6. Abid Khan
  7. Craig Mizzen
  8. Kannanganattu V Prasanth
  9. Slimane Ait-Si-Ali
  10. Taekjip Ha
  11. Supriya G Prasanth
(2015)
The preRC protein ORCA organizes heterochromatin by assembling histone H3 lysine 9 methyltransferases on chromatin
eLife 4:e06496.
https://doi.org/10.7554/eLife.06496

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https://doi.org/10.7554/eLife.06496

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