Poly(ADP-ribosyl)ation-dependent Transient Chromatin Decondensation and Histone Displacement following Laser Microirradiation*

  1. Michael J. Hendzel‡3
  1. From the ‡Department of Oncology, Faculty of Dentistry and Medicine, University of Alberta Alberta T6G 1Z2, Canada,
  2. the §Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892,
  3. the ‖Northern Ontario School of Medicine, Thunder Bay, Ontario P7B 5E1, Canada,
  4. the **Department of Biochemistry and Microbiology, University of Victoria, Victoria, B.C. V8W 3P6, Canada,
  5. the ‡‡Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, HKSAR, and
  6. the Oncology Axis, Laval University Hospital Research Center, CHUQ, Faculty of Medicine, Laval University, Quebec G1V 4G2, Canada
  1. ↵3 Supported as a senior scholar of Alberta Innovates Health Solutions. To whom correspondence should be addressed: Dept. of Oncology, University of Alberta, 11560 University Ave. NW, Edmonton, Alberta T6G 1Z2, Canada. Tel.: 780-432-8439; Fax: 780-432-8892; E-mail: mhendzel{at}ualberta.ca.

Abstract

Chromatin undergoes a rapid ATP-dependent, ATM and H2AX-independent decondensation when DNA damage is introduced by laser microirradiation. Although the detailed mechanism of this decondensation remains to be determined, the kinetics of decondensation are similar to the kinetics of poly(ADP-ribosyl)ation. We used laser microirradiation to introduce DNA strand breaks into living cells expressing a photoactivatable GFP-tagged histone H2B. We find that poly(ADP-ribosyl)ation mediated primarily by poly(ADP-ribose) polymerase 1 (PARP1) is responsible for the rapid decondensation of chromatin at sites of DNA damage. This decondensation of chromatin correlates temporally with the displacement of histones, which is sensitive to PARP inhibition and is transient in nature. Contrary to the predictions of the histone shuttle hypothesis, we did not find that histone H1 accumulated on poly(ADP-ribose) (PAR) in vivo. Rather, histone H1, and to a lessor extent, histones H2A and H2B were rapidly depleted from the sites of PAR accumulation. However, histone H1 returns to chromatin and the chromatin recondenses. Thus, the PARP-dependent relaxation of chromatin closely correlates with histone displacement.

Footnotes

  • ↵1 Holds a postdoctoral fellowship by the Alberta Cancer foundation and supported by the Bayrische Forschungsallianz.

  • ↵2 Canada Research Chair in Proteomics.

  • ↵* This work was supported in part by grants from the Canadian Institutes of Health Research, the Canadian Cancer Society, and the Alberta Cancer Research Institute. The authors declare that they have no conflicts of interest with the contents of this article.

  • Received October 5, 2015.
  • Revision received November 11, 2015.
View this article with LENS
Table of Contents

This Article

  1. First Published on November 11, 2015 doi: 10.1074/jbc.M115.694992 The Journal of Biological Chemistry 291, 1789-1802.
  1. » Abstract(Free)
  2. Full Text(Free)
  3. PDF(Free)
  4. All Versions of this Article:
    1. M115.694992v1
    2. 291/4/1789 (most recent)

Article Usage Stats

  1. Article Usage Statistics

Submit your work to JBC.

You'll be in good company.