Interactions of the karrikin signaling pathway with phytohormones and environmental signals in plants
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GRAPHICAL ABSTRACT
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PUBLIC SUMMARY
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Karrikins (KARs) are a class of butenolide compounds derived from smoke following vegetation burning.
KARs mimic an unknown phytohormone to regulate many aspects of development and environmental adaptation.
KAR signaling is perceived and transduced to trigger transcriptional reprogramming by one pathway.
KAR signaling interacts with many phytohormones and environmental signals.
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ABSTRACT
Karrikins (KARs), a class of butenolide compounds discovered in the smoke of burned vegetation, can mimic an unidentified phytohormone to regulate plant development and responses to environmental cues. The KAR signaling pathway is mediated by the 26S proteasome. Upon perception of KARs, the receptor of KARs, KARRIKIN INSENSITIVE 2 (KAI2), recruits the F-box protein, MORE AXILLARY GROWTH 2 (MAX2), and the repressor proteins, SUPPRESSOR OF MAX2 1 (SMAX1) and SMAX1-LIKE 2 (SMXL2), leading to the degradation of SMAX1 and SMXL2, which then reprograms the transcription of the KAR-responsive genes. This review focuses on the latest research progress regarding KAR signaling transduction, the identification of KAI2 ligands, and the crosstalk between KAR signaling, plant hormones, and environmental cues, providing new insights for future studies and applications in agriculture. -
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REFERENCES
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Cao S., Li X. and Wang L. (2025). Interactions of the karrikin signaling pathway with phytohormones and environmental signals in plants. The Innovation Life 3:100148. https://doi.org/10.59717/j.xinn-life.2025.100148
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Cao S., Li X. and Wang L. (2025). Interactions of the karrikin signaling pathway with phytohormones and environmental signals in plants. The Innovation Life 3:100148. https://doi.org/10.59717/j.xinn-life.2025.100148
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Content
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Figure 1.
Structures of KARs
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Figure 2.
A proposed model of KAR signaling pathway in Arabidopsis
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Figure 3.
Structures of GR24 isomers and candidate KLs
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Figure 4.
The interactions of the KAR signaling pathway with phytohormones
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Figure 5.
The interactions of KAR signaling pathway with light and warm temperature
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Figure 6.
The interaction of KAR signaling pathway with abiotic stress
