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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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VviNAC33 promotes organ de‐greening and represses vegetative growth during the vegetative‐to‐mature phase transition in grapevine
Summary Plants undergo several developmental transitions during their life cycle. In grapevine, a perennial woody fruit crop, the transition from vegetative/green‐to‐mature/woody growth involves transcriptomic reprogramming orchestrated by a small group of genes encoding regulators, but the underlying molecular mechanisms are not fully understood.We investigated the function of the transcriptional regulatorVviNAC33by generating and characterizing transgenic overexpressing grapevine lines and a chimeric repressor, and by exploring its putative targets through a DNA affinity purification sequencing (DAP‐seq) approach combined with transcriptomic data.We demonstrated that VviNAC33 induces leaf de‐greening, inhibits organ growth and directly activates the expression ofSTAY‐GREEN PROTEIN 1(SGR1), which is involved in Chl and photosystem degradation, andAUTOPHAGY 8f(ATG8f), which is involved in the maturation of autophagosomes. Furthermore, we show that VviNAC33 directly inhibitsAUXIN EFFLUX FACILITATOR PIN1,RopGEF1andATP SYNTHASE GAMMA CHAIN 1T(ATPC1), which are involved in photosystem II integrity and activity.Our results show that VviNAC33 plays a major role in terminating photosynthetic activity and organ growth as part of a regulatory network governing the vegetative‐to‐mature phase transition.
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- Award ID(s):
- 1916804
- PAR ID:
- 10450713
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 231
- Issue:
- 2
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 726-746
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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