Oxygen-dependent proteolysis regulates the stability of angiosperm polycomb repressive complex 2 subunit VERNALIZATION2

Gibbs, Daniel J.; Tedds, Hannah M.; Labandera, Anne-Marie; Bailey, Mark; White, Mark D.; Hartman, Sjon; Sprigg, Colleen; Mogg, Sophie L.; Osborne, Rory; Dambire, Charlene; Boeckx, Tinne; Paling, Zachary; Voesenek, Laurentius A.C.J.; Flashman, Emily; Holdsworth, Michael J.

Abstract

The polycomb repressive complex 2 (PRC2) regulates epigenetic gene repression in eukaryotes. Mechanisms controlling its developmental specificity and signal-responsiveness are poorly understood. Here, we identify an oxygen-sensitive N-terminal (N-) degron in the plant PRC2 subunit VERNALIZATION(VRN)2, a homolog of animal Su(z)12, that promotes its degradation via the N-end rule pathway. We provide evidence that this N-degron arose early during angiosperm evolution via gene duplication and N-terminal truncation, facilitating expansion of PRC2 function in flowering plants. We show that proteolysis via the N-end rule pathway prevents ectopic VRN2 accumulation, and that hypoxia and long-term cold exposure lead to increased VRN2 abundance, which we propose may be due to inhibition of VRN2 turnover via its N-degron. Furthermore, we identify an overlap in the transcriptional responses to hypoxia and prolonged cold, and show that VRN2 promotes tolerance to hypoxia. Our work reveals a mechanism for post-translational regulation of VRN2 stability that could potentially link environmental inputs to the epigenetic control of plant development.

Citation

Gibbs, D. J., Tedds, H. M., Labandera, A., Bailey, M., White, M. D., Hartman, S., …Holdsworth, M. J. (2018). Oxygen-dependent proteolysis regulates the stability of angiosperm polycomb repressive complex 2 subunit VERNALIZATION2. Nature Communications, 9, Article 5438. https://doi.org/10.1038/s41467-018-07875-7

• Journal Article Type: Article
• Acceptance Date: Dec 4, 2018
• Online Publication Date: Dec 21, 2018
• Publication Date: Dec 21, 2018
• Deposit Date: Dec 6, 2018
• Publicly Available Date: Dec 21, 2018
• Journal: Nature Communications
• Electronic ISSN: 2041-1723
• Publisher: Nature Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 9
• Article Number: 5438
• DOI: https://doi.org/10.1038/s41467-018-07875-7
• Public URL: https://nottingham-repository.worktribe.com/output/1379035