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Updated: Oct 22, 2025
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In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
Published on: July 25, 2019
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H2A ubiquitination is essential for Polycomb Repressive Complex 1-mediated gene regulation in Marchantia polymorpha
Shujing Liu1, Minerva S Trejo-Arellano2,3, Yichun Qiu2,4
1Department of Plant Biology, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 75007, Uppsala, Sweden. shujing.liu@slu.se.
Genome Biology
|September 1, 2021
Summary
Polycomb repressive complex 1 (PRC1) ubiquitination of H2A is essential for gene silencing in plants. This process is required for H3K27me3 deposition and PRC1-mediated transcriptional regulation of genes and transposable elements.
Area of Science:
- Plant molecular biology
- Epigenetics
- Chromatin regulation
Background:
- Polycomb repressive complex 1 (PRC1) and PRC2 are key chromatin regulators.
- H3 lysine 27 tri-methylation (H3K27me3) by PRC2 is crucial for transcriptional repression.
- The role of H2A ubiquitination (H2Aub) in plant Polycomb systems is not well understood.
Purpose of the Study:
- To investigate the necessity of H2Aub for gene regulation in the liverwort Marchia polymorpha.
- To determine if PRC1-catalyzed H2Aub is essential for the Polycomb repressive system in plants.
Main Methods:
- Generated point mutations in H2A to block ubiquitination by PRC1.
- Assessed H3K27me3 levels in generated mutants.
- Compared transcriptome data between H2A and PRC1 subunit mutants.
Main Results:
- Mutants lacking H2Aub exhibited reduced H3K27me3 levels at target sites.
- H2Aub is essential for Polycomb system function, similar to PRC1 subunit mutants.
- H2Aub influences PRC1-mediated transcriptional levels of genes and transposable elements.
Conclusions:
- H2Aub directly contributes to H3K27me3 deposition.
- H2Aub is required for PRC1-mediated transcriptional changes in Marchantia.
- This study clarifies the role of H2Aub in plant epigenetic regulation.
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