Abstract

Over 80% of diffuse intrinsic pontine gliomas (DIPGs) harbor a point mutation in histone H3.3 where lysine 27 is substituted with methionine (H3.3K27M); however, how the mutation affects kinetics and function of PcG proteins remains elusive. We demonstrate that H3.3K27M prolongs the residence time and search time of Ezh2, but has no effect on its fraction bound to chromatin. In contrast, H3.3K27M has no effect on the residence time of Cbx7, but prolongs its search time and decreases its fraction bound to chromatin. We show that increasing expression of Cbx7 inhibits the proliferation of DIPG cells and prolongs its residence time. Our results highlight that the residence time of PcG proteins directly correlates with their functions and the search time of PcG proteins is critical for regulating their genomic occupancy. Together, our data provide mechanisms in which the cancer-causing histone mutation alters the binding and search dynamics of epigenetic complexes.

Details

Title
Live-cell single-molecule dynamics of PcG proteins imposed by the DIPG H3.3K27M mutation
Author
Roubina Tatavosian 1 ; Huy Nguyen Duc 1 ; Huynh, Thao Ngoc 1 ; Fang, Dong 2 ; Schmitt, Benjamin 3 ; Shi, Xiaodong 4 ; Deng, Yiming 4 ; Phiel, Christopher 5 ; Yao, Tingting 3 ; Zhang, Zhiguo 2 ; Wang, Haobin 1 ; Ren, Xiaojun 1 

 Department of Chemistry, University of Colorado Denver, Denver, CO, USA 
 Institute for Cancer Genetics, Columbia University, New York, NY, USA 
 Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA 
 Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI, USA 
 Department of Integrative Biology, University of Colorado Denver, Denver, CO, USA 
Pages
1-16
Publication year
2018
Publication date
May 2018
Publisher
Nature Publishing Group
e-ISSN
20411723
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2044308932
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.