SlWRKY2 orchestrates cold tolerance via phytochromes interaction and SlPIF4 stabilization in tomato

Area of Science:

• Plant molecular biology
• Environmental stress response
• Signal transduction pathways

Background:

• Plants integrate light and temperature signals for stress responses.
• Molecular mechanisms of light-temperature signal crosstalk are not fully understood.
• Phytochromes are key photoreceptors mediating light responses.

Purpose of the Study:

• Identify molecular players linking light perception and cold stress adaptation in tomato.
• Elucidate the role of transcription factor SlWRKY2 in integrating light and cold signals.
• Investigate the regulatory network involving SlWRKY2, phytochromes, and SlPIF4.

Main Methods:

• Genetic analyses in tomato (Solanum lycopersicum).
• Protein-protein interaction studies (co-immunoprecipitation).
• Analysis of gene expression under varying light and cold conditions.
• Investigated liquid-liquid phase separation (LLPS) of SlWRKY2.

Main Results:

• SlWRKY2 acts as a crucial hub connecting phytochrome-mediated light sensing with cold adaptation.
• Low red/far-red light ratios induce SlWRKY2, with SlphyA promoting and SlphyB repressing its expression.
• SlWRKY2 interacts with SlphyB and SlphyA, and stabilizes/activates SlPIF4, enhancing cold tolerance via SlCBFs.

Conclusions:

• A novel SlphyB/A-SlWRKY2-SlPIF4 signaling module integrates light quality and cold stress.
• This module fine-tunes cold adaptation by modulating SlPIF4 activity and SlCBF expression.
• Findings advance understanding of environmental cue integration in plant stress responses.