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.-M., Bailey, M., White, M. D., Hartman, S., Sprigg, C., Mogg, S. L., Osborne, R., Dambire, C., Boeckx, T., Paling, Z., Voesenek, L. A., Flashman, E., & 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
• Contract Date: Dec 21, 2018