Oxygen-dependent proteolysis regulates the stability of angiosperm polycomb repressive complex 2 subunit VERNALIZATION 2. Issue 1 (December 2018)

• Record Type: Journal Article
• Authors: Gibbs, Daniel; Tedds, Hannah; Labandera, Anne-Marie; Bailey, Mark; White, Mark; Hartman, Sjon; Sprigg, Colleen; Mogg, Sophie; Osborne, Rory; Dambire, Charlene; Boeckx, Tinne; Paling, Zachary; Voesenek, Laurentius; Flashman, Emily; Holdsworth, Michael
• Is Part Of: Nature communications. Volume 9:Issue 1(2018)
• Page Start: 1
• Page End: 11
• Publication Date: 2018-12
• Subjects: Biology -- Periodicals; Physical sciences -- Periodicals; 505
• DOI: 10.1038/s41467-018-07875-7
• Languages: English
• ISSNs: 2041-1723

Abstract

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. VRN2 is a Polycomb Repressive Complex 2 subunit, best known as a regulator of vernalization that accumulates during prolonged cold. Here Gibbset al . show that VRN2 is degraded via the N-end rule pathway, which prevents ectopic accumulation of VRN2 in the absence of appropriate environmental stimuli.