Abstract

Transcription by RNA polymerase V (Pol V) in plants is required for RNA-directed DNA methylation, leading to transcriptional gene silencing. Global chromatin association of Pol V requires components of the DDR complex DRD1, DMS3 and RDM1, but the assembly process of this complex and the underlying mechanism for Pol V recruitment remain unknown. Here we show that all DDR complex components co-localize with Pol V, and we report the cryoEM structures of two complexes associated with Pol V recruitment—DR (DMS3-RDM1) and DDR′ (DMS3-RDM1-DRD1 peptide), at 3.6 Å and 3.5 Å resolution, respectively. RDM1 dimerization at the center frames the assembly of the entire complex and mediates interactions between DMS3 and DRD1 with a stoichiometry of 1 DRD1:4 DMS3:2 RDM1. DRD1 binding to the DR complex induces a drastic movement of a DMS3 coiled-coil helix bundle. We hypothesize that both complexes are functional intermediates that mediate Pol V recruitment.

Details

Title
CryoEM structures of Arabidopsis DDR complexes involved in RNA-directed DNA methylation
Author
Somsakul Pop Wongpalee 1   VIAFID ORCID Logo  ; Liu, Shiheng 2   VIAFID ORCID Logo  ; Gallego-Bartolomé, Javier 3 ; Leitner, Alexander 4   VIAFID ORCID Logo  ; Aebersold, Ruedi 5   VIAFID ORCID Logo  ; Liu, Wanlu 6 ; Yen, Linda 3 ; Nohales, Maria A 7 ; Kuo, Peggy Hsuanyu 3 ; Vashisht, Ajay A 8 ; Wohlschlegel, James A 8 ; Feng, Suhua 3 ; Kay, Steve A 7 ; Z Hong Zhou 2   VIAFID ORCID Logo  ; Jacobsen, Steven E 9   VIAFID ORCID Logo 

 Department of Molecular, Cellular and Developmental Biology, University of California, Los Angeles (UCLA), Los Angeles, CA, USA; Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand 
 Department of Microbiology, Immunology and Molecular Genetics, UCLA, Los Angeles, CA, USA; California NanoSystems Institute (CNSI), UCLA, Los Angeles, CA, USA 
 Department of Molecular, Cellular and Developmental Biology, University of California, Los Angeles (UCLA), Los Angeles, CA, USA 
 Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, Zürich, Switzerland 
 Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, Zürich, Switzerland; Faculty of Science, University of Zürich, Zürich, Switzerland 
 Department of Molecular, Cellular and Developmental Biology, University of California, Los Angeles (UCLA), Los Angeles, CA, USA; Zhejiang University-University of Edinburgh Institute, Zhejiang University School of Medicine, Hangzhou, P. R. China 
 Keck School of Medicine, University of Southern California, Los Angeles, CA, USA 
 Department of Biological Chemistry, UCLA, Los Angeles, CA, USA 
 Department of Molecular, Cellular and Developmental Biology, University of California, Los Angeles (UCLA), Los Angeles, CA, USA; Howard Hughes Medical Institute (HHMI), UCLA, Los Angeles, CA, USA 
Pages
1-12
Publication year
2019
Publication date
Sep 2019
Publisher
Nature Publishing Group
e-ISSN
20411723
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2283282924
Copyright
© 2019. 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.