DELLA proteins recruit the Mediator complex subunit MED15 to coactivate transcription in land plants
Author(s)
Hernández-García, Jorge
Serrano-Mislata, Antonio
Lozano-Quiles, María
Úrbez, Cristina
Nohales, María A
Type
Journal Article
Abstract
DELLA proteins are negative regulators of the gibberellin response pathway in angiosperms, acting as central hubs that interact with hundreds of transcription factors (TFs) and regulators to modulate their activities. While the mechanism of TF sequestration by DELLAs to prevent DNA binding to downstream targets has been extensively documented, the mechanism that allows them to act as coactivators remains to be understood. Here, we demonstrate that DELLAs directly recruit the Mediator complex to specific loci in Arabidopsis, facilitating transcription. This recruitment involves DELLA amino-terminal domain and the conserved MED15 KIX domain. Accordingly, partial loss of MED15 function mainly disrupted processes known to rely on DELLA coactivation capacity, including cytokinin-dependent regulation of meristem function and skotomorphogenic response, gibberellin metabolism feedback, and flavonol production. We have also found that the single DELLA protein in the liverwort Marchantia polymorpha is capable of recruiting MpMED15 subunits, contributing to transcriptional coactivation. The conservation of Mediator-dependent transcriptional coactivation by DELLA between Arabidopsis and Marchantia implies that this mechanism is intrinsic to the emergence of DELLA in the last common ancestor of land plants.
Date Issued
2024-05-07
Date Acceptance
2024-03-27
Citation
Proceedings of the National Academy of Sciences of USA, 2024, 121 (19)
ISSN
0027-8424
Publisher
National Academy of Sciences
Journal / Book Title
Proceedings of the National Academy of Sciences of USA
Volume
121
Issue
19
Copyright Statement
Copyright © 2024 the Author(s). Published by PNAS. This article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND).
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/38696472
Subjects
Arabidopsis
Arabidopsis Proteins
Gene Expression Regulation, Plant
Gibberellins
Marchantia
Mediator Complex
Plant Proteins
Transcription Factors
Transcription, Genetic
DELLA proteins
gibberellins
hormone signaling
Mediator
transactivation
Publication Status
Published
Coverage Spatial
United States
Article Number
e2319163121
Date Publish Online
2024-05-02