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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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Vegetative phase change causes age‐dependent changes in phenotypic plasticity
Summary Phenotypic plasticity allows organisms to optimize traits for their environment. As organisms age, they experience diverse environments that benefit from varying degrees of phenotypic plasticity. Developmental transitions can control these age‐dependent changes in plasticity, and as such, the timing of these transitions can determine when plasticity changes in an organism.Here, we investigate how the transition from juvenile‐to adult‐vegetative development known as vegetative phase change (VPC) contributes to age‐dependent changes in phenotypic plasticity and how the timing of this transition responds to environment using both natural accessions and mutant lines in the model plantArabidopsis thaliana.We found that the adult phase of vegetative development has greater plasticity in leaf morphology than the juvenile phase and confirmed that this difference in plasticity is caused by VPC using mutant lines. Furthermore, we found that the timing of VPC, and therefore the time when increased plasticity is acquired, varies significantly across genotypes and environments.The consistent age‐dependent changes in plasticity caused by VPC suggest that VPC may be adaptive. This genetic and environmental variation in the timing of VPC indicates the potential for population‐level adaptive evolution of VPC.
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- PAR ID:
- 10441889
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 240
- Issue:
- 2
- ISSN:
- 0028-646X
- Format(s):
- Medium: X Size: p. 613-625
- Size(s):
- p. 613-625
- Sponsoring Org:
- National Science Foundation
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