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Updated: May 27, 2026
12:36
Chromatin Immunoprecipitation Assay for the Identification of Arabidopsis Protein-DNA Interactions In Vivo
Published on: January 14, 2016
The TOPLESS interactome: a framework for gene repression in Arabidopsis
Barry Causier1, Mary Ashworth, Wenjia Guo
1Centre for Plant Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom.
Plant Physiology
|November 9, 2011
Summary
TOPLESS (TPL) and TPL-related (TPR) corepressors in plants interact with transcription factors to regulate gene expression. This study identifies novel interactions and mechanisms for TPL/TPR-mediated repression in various plant processes.
Area of Science:
- Plant Molecular Biology
- Gene Regulation
- Epigenetics
Background:
- Groucho/Tup1 corepressors mediate transcriptional repression in animals and yeast.
- Plants possess two groups of Groucho/Tup1-like corepressors: LEUNIG/LEUNIG_HOMOLOG and TOPLESS (TPL)/TPL-related (TPR) proteins.
- The specific roles and interacting partners of TPL/TPR corepressors in plants remain largely uncharacterized.
Purpose of the Study:
- To identify proteins that interact with TPL/TPR corepressors using high-throughput yeast two-hybrid screens.
- To elucidate the functional roles of TPL/TPR corepressors in diverse plant biological processes.
- To understand the molecular mechanisms underlying TPL/TPR-mediated transcriptional repression.
Main Methods:
- High-throughput yeast two-hybrid (Y2H) screening to identify protein-protein interactions.
- Bioinformatic analysis of interaction data to identify enriched transcription factor families.
- Biological validation of TPL/TPR involvement in specific plant processes, including hormone signaling and flowering time control.
- Analysis of repression domain (RD) sequences in transcription factor interactions with TPL/TPR.
Main Results:
- TPL/TPR corepressors predominantly interact directly with specific transcription factors, many previously linked to repression.
- Identified interactions suggest TPL/TPR involvement in hormone signaling (auxin, jasmonic acid), stress responses, and flowering time control.
- All known repression domain (RD) sequences in Arabidopsis transcription factors were enriched among TPL/TPR interactors, and novel interactions were found.
- The presence of RD sequences is essential for TPL/TPR recruitment to target genes.
Conclusions:
- The TPL/TPR corepressor family plays a significant role in modulating gene expression across diverse plant developmental and environmental responses.
- Interaction data provide a framework for understanding TPL/TPR-dependent transcriptional repression mechanisms.
- This study identifies novel repressive transcription factors, corepressor interactions, and repression mechanisms, expanding the known scope of TPL/TPR function in plants.
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