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Summary The juvenile‐to‐adult vegetative phase change in flowering plants is mediated by a decrease in miR156 levels. Downregulation ofMIR156A/MIR156C, the two major sources of miR156, is accompanied by a decrease in acetylation of histone 3 lysine 27 (H3K27ac) and an increase in trimethylation of H3K27 (H3K27me3) atMIR156A/MIR156CinArabidopsis.Here, we show that histone deacetylase 9 (HDA9) is recruited toMIR156A/MIR156Cduring the juvenile phase and associates with the CHD3 chromatin remodeler PICKLE (PKL) to erase H3K27ac atMIR156A/MIR156C.H2Aub and H3K27me3 become enriched atMIR156A/MIR156C, and the recruitment of Polycomb Repressive Complex 2 (PRC2) toMIR156A/MIR156Cis partially dependent on the activities of PKL and HDA9.Our results suggest that PKL associates with histone deacetylases to erase H3K27ac and promote PRC1 and PRC2 activities to mediate vegetative phase change and maintain plants in the adult phase after the phase transition.
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DEK domain‐containing proteins control flowering time in Arabidopsis
Summary Evolutionarily conserved DEK domain‐containing proteins have been implicated in multiple chromatin‐related processes, mRNA splicing and transcriptional regulation in eukaryotes.Here, we show that two DEK proteins, DEK3 and DEK4, control the floral transition inArabidopsis. DEK3 and DEK4 directly associate with chromatin of related flowering repressors,FLOWERING LOCUS C(FLC), and its two homologs,MADS AFFECTING FLOWERING4(MAF4) andMAF5, to promote their expression.The binding of DEK3 and DEK4 to a histone octamerin vivoaffects histone modifications atFLC,MAF4andMAF5loci. In addition, DEK3 and DEK4 interact with RNA polymerase II and promote the association of RNA polymerase II withFLC,MAF4andMAF5chromatin to promote their expression.Our results show that DEK3 and DEK4 directly interact with chromatin to facilitate the transcription of key flowering repressors and thus prevent precocious flowering inArabidopsis.
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- Award ID(s):
- 1656764
- PAR ID:
- 10450167
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 231
- Issue:
- 1
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 182-192
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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