Repression by the Arabidopsis TOPLESS corepressor requires association with the core Mediator complex
Abstract
The plant corepressor TOPLESS (TPL) is recruited to a large number of loci that are selectively induced in response to developmental or environmental cues, yet the mechanisms by which it inhibits expression in the absence of these stimuli is poorly understood. Previously, we had used the N-terminus of Arabidopsis thaliana TPL to enable repression of a synthetic auxin response circuit in Saccharomyces cerevisiae (yeast). Here, we leveraged the yeast system to interrogate the relationship between TPL structure and function, specifically scanning for repression domains. We identified a potent repression domain in Helix 8 located within the CRA domain, which directly interacted with the Mediator middle module subunits Med21 and Med10. Interactions between TPL and Mediator were required to fully repress transcription in both yeast and plants. In contrast, we found that multimer formation, a conserved feature of many corepressors, had minimal influence on the repression strength of TPL.
Data availability
All flow cytometry data is deposited at https://flowrepository.org/. Repository IDS: FR-FCM-Z2GM, FR-FCM-Z2GR, FR-FCM-Z2GQ, FR-FCM-Z2GX, FR-FCM-Z2GT, FR-FCM-Z2W2. All protein interactions have been deposited to IntAct, under the accession code, IM-28972. All code is available through Github: https://github.com/achillobator/TPL_Structure_Function/
-
TPL Helix-By-Helix deletion seriesFlow Repository, FR-FCM-Z2GM.
-
TPL Helix-By-Helix deletion series 2Flow Repository, FR-FCM-Z2GR.
-
TPL Helix-By-Helix deletion series 3Flow Repository, FR-FCM-Z2GT.
-
TPL Helix-By-Helix deletion series 4Flow Repository, FR-FCM-Z2W2.
-
Repression by the Arabidopsis TOPLESS corepressor requires association with the core Mediator complexEBI IntAct Molecular Interaction Database, IM-28972.
Article and author information
Author details
Funding
National Institutes of Health (GM107084)
- Alexander R Leydon
- Hardik P Gala
- Sabrina Gilmour
- Samuel Juarez-Solis
- Mollye L Zahler
- Joseph E Zemke
- Jennifer L Nemhauser
Howard Hughes Medical Institute
- Alexander R Leydon
- Wei Wang
- Hardik P Gala
- Sabrina Gilmour
- Samuel Juarez-Solis
- Mollye L Zahler
- Joseph E Zemke
- NIng Zheng
- Jennifer L Nemhauser
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Leydon et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 3,935
- views
-
- 519
- downloads
-
- 52
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Further reading
-
- Chromosomes and Gene Expression
RNA interference (RNAi) is a conserved pathway that utilizes Argonaute proteins and their associated small RNAs to exert gene regulatory function on complementary transcripts. While the majority of germline-expressed RNAi proteins reside in perinuclear germ granules, it is unknown whether and how RNAi pathways are spatially organized in other cell types. Here, we find that the small RNA biogenesis machinery is spatially and temporally organized during Caenorhabditis elegans embryogenesis. Specifically, the RNAi factor, SIMR-1, forms visible concentrates during mid-embryogenesis that contain an RNA-dependent RNA polymerase, a poly-UG polymerase, and the unloaded nuclear Argonaute protein, NRDE-3. Curiously, coincident with the appearance of the SIMR granules, the small RNAs bound to NRDE-3 switch from predominantly CSR-class 22G-RNAs to ERGO-dependent 22G-RNAs. NRDE-3 binds ERGO-dependent 22G-RNAs in the somatic cells of larvae and adults to silence ERGO-target genes; here we further demonstrate that NRDE-3-bound, CSR-class 22G-RNAs repress transcription in oocytes. Thus, our study defines two separable roles for NRDE-3, targeting germline-expressed genes during oogenesis to promote global transcriptional repression, and switching during embryogenesis to repress recently duplicated genes and retrotransposons in somatic cells, highlighting the plasticity of Argonaute proteins and the need for more precise temporal characterization of Argonaute-small RNA interactions.
-
- Chromosomes and Gene Expression
- Genetics and Genomics
A new method for mapping torsion provides insights into the ways that the genome responds to the torsion generated by RNA polymerase II.