The membrane-localized protein kinase MAP4K4/TOT3 regulates thermomorphogenesis
Lam Dai Vu1,2,3,4, Xiangyu Xu1,2, Tingting Zhu1,2
1Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052, Ghent, Belgium.
Nature Communications
|May 15, 2021
Summary
Researchers identified MITOGEN-ACTIVATED PROTEIN KINASE KINASE KINASE KINASE4 (MAP4K4), also known as TARGET OF TEMPERATURE3 (TOT3), as a key regulator of plant heat response. This discovery in Arabidopsis and wheat offers insights into crop resilience for a changing climate.
Area of Science:
- Plant Biology
- Molecular Biology
- Climate Change Adaptation
Background:
- Plants exhibit thermomorphogenesis, increasing organ elongation for cooling under warm temperatures.
- Regulation of thermomorphogenesis has primarily been linked to light signaling pathways.
- Understanding conserved regulators is crucial for crop adaptation to climate change.
Purpose of the Study:
- To identify conserved regulators of thermomorphogenesis in flowering plants.
- To investigate the role of MAP4K4/TOT3 in plant thermal responses.
- To explore the connection between TOT3 and brassinosteroid signaling.
Main Methods:
- Comparative analysis of protein phosphorylation changes in dicots and monocots under warm temperatures.
- Genetic studies in *Arabidopsis thaliana* to assess the function of MAP4K4/TOT3.
- Phenotypic analysis of wheat under varying temperature conditions.
Main Results:
- MITOGEN-ACTIVATED PROTEIN KINASE KINASE KINASE KINASE4 (MAP4K4)/TARGET OF TEMPERATURE3 (TOT3) was identified as a regulator of thermomorphogenesis.
- MAP4K4/TOT3 influences thermomorphogenesis by interacting with brassinosteroid signaling in *Arabidopsis thaliana*.
- TOT3 demonstrated a conserved role in thermal response in wheat, a monocot crop.
Conclusions:
- TOT3 is a conserved regulator of thermomorphogenesis across different plant species.
- The discovery of TOT3's role expands the understanding of thermomorphogenesis beyond light signaling.
- Conserved thermal regulators like TOT3 are vital for developing climate-resilient crops and ensuring food security.
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