An Importin Protein SlIMPA3 Interacts with SlLCD1 and Regulates Tomato Fruit Ripening
Min Zhang1, Xiang-Jun Peng1, Nan-Nan Liu1
1School of Food and Biological Engineering, Hefei University of Technology, Hefei 230009, China.
Journal of Agricultural and Food Chemistry
|January 2, 2025
Summary
The nuclear import receptor SlIMPA3 facilitates the nuclear entry of cysteine desulfhydrase SlLCD1 in tomatoes. SlIMPA3 mutations accelerate fruit ripening and leaf senescence by mislocalizing SlLCD1.
Area of Science:
- Plant Molecular Biology
- Plant Physiology
- Biochemistry
Background:
- Nuclear localization of cysteine desulfhydrase (SlLCD1) is crucial for hydrogen sulfide production in tomatoes.
- The mechanism of SlLCD1 nuclear import remains unclear.
Purpose of the Study:
- To elucidate the mechanism of SlLCD1 nuclear localization.
- To investigate the role of SlLCD1 nuclear import in tomato fruit ripening and leaf senescence.
Main Methods:
- Virus-induced gene silencing (VIGS) and CRISPR/Cas9 gene editing to silence or mutate SlIMPA3.
- GFP tagging to track protein localization.
- Analysis of fruit ripening, chlorophyll degradation, carotenoid accumulation, and gene expression.
Main Results:
- SlLCD1 specifically interacts with the nuclear import receptor importin α3 (SlIMPA3).
- SlIMPA3 silencing or mutation accelerates fruit ripening and leaf senescence, associated with increased hydrogen peroxide.
- SlIMPA3 mediates the nuclear localization of SlLCD1; its absence causes SlLCD1 mislocalization to the cytoplasm.
Conclusions:
- SlIMPA3 is essential for SlLCD1 nuclear import and acts as a negative regulator of tomato fruit ripening and leaf senescence.
- Disruption of SlLCD1 nuclear localization due to SlIMPA3 mutation affects reactive oxygen species homeostasis, leading to premature senescence and ripening.
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