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Updated: Jun 29, 2026
07:42
Rapid Analysis of Circadian Phenotypes in Arabidopsis Protoplasts Transfected with a Luminescent Clock Reporter
Published on: September 17, 2016
Vernalisation-induced changes to the Arabidopsis circadian clock require Polycomb Repressive Complex 2 and are
Stephanie S I Williams1, Miguel Montez1, Emily Edwards1
1John Innes Centre, Norwich Research Park, Norwich NR4 7UH, U.K.
Plant & Cell Physiology
|June 27, 2026
Summary
Winter cold exposure stably alters the plant circadian clock, influencing flowering time through epigenetic memory. This mechanism, mediated by Polycomb Repressive Complex 2 (PRC2), prepares plants for seasonal changes.
Area of Science:
- Plant biology
- Epigenetics
- Circadian rhythms
Background:
- Plant flowering is regulated by vernalization (cold) and photoperiod (day-length).
- The circadian clock influences both pathways, but their interactions and clock's role in vernalization are not fully understood.
Purpose of the Study:
- To investigate how vernalization affects the plant circadian clock.
- To understand the molecular mechanisms underlying vernalization-induced clock changes and their impact on flowering.
Main Methods:
- Analysis of circadian clock gene expression after prolonged cold treatment (vernalization).
- Investigating the role of epigenetic regulators, specifically Polycomb Repressive Complex 2 (PRC2), in mediating these changes.
- Assessing the stability of clock alterations upon return to warm conditions.
Main Results:
- Vernalization induces stable, lasting changes in specific circadian clock genes.
- These clock alterations are linked to changes in clock-controlled outputs, including photoperiodic flowering.
- The epigenetic regulator PRC2, but not FRI or FLC genes, is required for these vernalization-induced clock modifications.
Conclusions:
- Prolonged cold exposure establishes an epigenetic memory within the plant circadian clock.
- This epigenetic memory mechanism, involving PRC2, potentially prepares plants for seasonal transitions and optimizes flowering time.
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