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Spatiotemporal regulation of gene expression by polycomb repressive complex 2 (PRC2) is critical for animal and plant development. The Arabidopsis fertilization independent seed (FIS)-PRC2 complex functions specifically during plant reproduction from gametogenesis to seed development. After a double fertilization event, triploid endosperm proliferates early, followed by the growth of a diploid embryo, which replaces the endosperm in Arabidopsis and many dicots. Key genes critical for endosperm proliferation such as IKU2 and MINI3 are activated after fertilization. Here we report that two MADS-box AGAMOUS-LIKE (AGL) proteins associate with the key endosperm proliferation loci and recruit the FIS-PRC2 repressive complex at 4–5 days after pollination (DAP). Interestingly, AGL9 and AGL15 only accumulate toward the end of endosperm proliferation at 4–5 DAP and promote the deposition of H3K27me3 marks at key endosperm proliferation loci. Disruption of AGL9 and AGL15 or overexpression of AGL9 or AGL15 significantly influence endosperm proliferation and cellularization. Genome-wide analysis with cleavage Under Targets and tagmentation (CUT&Tag) sequencing and RNA sequencing revealed the landscape of endosperm H3K27me3 marks and gene expression profiles in Col-0 and agl9 agl15. CUT&Tag qPCR also demonstrated the occupancy of the two MADS-box proteins and FIS-PRC2 on a few representative target loci. Our studies suggest that MADS-box proteins could potentially recruit PRC2 to regulate many other developmental processes in plants or even in fungi and animals.
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This content will become publicly available on April 1, 2026
Dynamic control of H2A.Zub and H3K27me3 by ambient temperature during cell fate determination in Arabidopsis
Crucial to plant development, ambient temperature triggers intricate mechanisms enabling adaptive responses to temperature variations. The precise coordination of chromatin modifications in shaping cell developmental fate under diverse temperatures remains elusive. Our study, integrating comprehensive transcriptome, epigenome profiling, and genetics, demonstrates that lower ambient temperature (16°C) partially restores developmental defects caused by H3K27me3 loss in prc2 mutants by specifically depositing H2A.Zub at ectopically expressed embryonic genes in Arabidopsis, such as ABA INSENSITIVE 3 (ABI3) and LEAFY COTYLEDON 1 (LEC1). This deposition leads to downregulation of these genes and compensates for H3K27me3 depletion. Polycomb-repressive complex 1 (PRC1)-catalyzed H2A.Zub and PRC2-catalyzed H3K27me3 play roles in silencing transcription of embryonic genes for post-germination development. Low-temperature-induced reduction of TOE1 protein level decelerates H2A.Z turnover at specific loci, sustaining repression of embryonic genes and alleviating requirement for PRC2-H3K27me3 at post-germination stage. Our findings offer mechanistic insights into the cooperative epigenetic layers, facilitating plant adaptation to varying environmental temperatures.
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- Award ID(s):
- 2224729
- PAR ID:
- 10626520
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Developmental Cell
- ISSN:
- 1534-5807
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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