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Updated: Aug 14, 2025
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Design and Analysis of Temperature Preference Behavior and its Circadian Rhythm in Drosophila
Published on: January 13, 2014
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ZTL regulates thermomorphogenesis through TOC1 and PRR5.
Dain Seo1, Jeonghyang Park1, Jeeyoon Park1
1Department of Life Sciences, Korea University, Seoul, Korea.
Plant, Cell & Environment
|January 19, 2023
Summary
High temperatures trigger plant growth changes via thermomorphogenesis. The ZEITLUPE (ZTL) protein controls this by degrading TOC1 and PRR5, enhancing heat response sensitivity.
Area of Science:
- Plant Biology
- Molecular Biology
- Chronobiology
Background:
- Plants adapt to heat stress using thermomorphogenesis, involving stem elongation and leaf growth.
- The circadian clock, specifically evening-expressed TIMING OF CAB EXPRESSION1 (TOC1) and PSEUDO-RESPONSE REGULATORS5 (PRR5), regulates this process.
- PHYTOCHROME INTERACTING FACTOR4 (PIF4) promotes thermoresponsive growth and is inhibited by TOC1 and PRR5.
Purpose of the Study:
- To elucidate the molecular mechanisms by which ZEITLUPE (ZTL) regulates thermoresponsive growth.
- To investigate the role of ZTL in the interaction between the circadian clock and heat stress response pathways.
Main Methods:
- Genetic analysis in Arabidopsis thaliana.
- Investigating protein interactions and stability.
- Analyzing gene expression of PIF4 target genes.
Main Results:
- ZTL regulates both PIF4 activity and expression.
- ztl mutants show accumulated TOC1/PRR5 and unresponsive PIF4 target genes at high temperatures.
- Mutations in TOC1/PRR5 restore thermoresponsive growth in ztl mutants.
- Heat-shock protein 90 interacts with the ZTL-TOC1/PRR5 module.
- ZTL protein stability increases at high temperatures.
Conclusions:
- ZTL enhances thermoresponsive growth by promoting TOC1 and PRR5 degradation.
- This ZTL-mediated degradation increases plant sensitivity to high temperatures.
- The ZTL-TOC1/PRR5 signaling module is a key component in plant thermomorphogenesis.
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