The 14-3-3 Protein SlTFT1 Accelerates Tomato Fruit Ripening by Binding and Stabilising YFT1 in the Ethylene...

Area of Science:

• Plant Biology
• Molecular Biology
• Biochemistry

Background:

• Ethylene is crucial for tomato (Solanum lycopersicum) fruit ripening.
• The YELLOW-FRUITED TOMATO1 (YFT1) protein is a key regulator in ethylene signaling during ripening.
• The precise molecular mechanisms of YFT1-mediated ethylene signaling remain unclear.

Purpose of the Study:

• To identify novel YFT1-interacting proteins.
• To elucidate the molecular mechanism of YFT1-mediated ethylene signaling in tomato fruit ripening.
• To characterize the role of SlTFT1 in regulating fruit ripening.

Main Methods:

• Yeast two-hybrid screens to identify interacting proteins.
• In vitro and in vivo interaction assays (e.g., bimolecular fluorescence complementation).
• Triple response assays, gene expression analysis, phenotypic and biochemical analysis of overexpression and mutant lines, co-expression, and western blotting.

Main Results:

• Identified and confirmed SlTFT1 as a YFT1-interacting protein, binding to the YFT1 carboxyl terminus.
• SlTFT1 positively regulates ethylene signaling in a YFT1-dependent manner.
• SlTFT1 accelerates fruit ripening, ethylene emission, chromoplast development, and lycopene accumulation, with YFT1 being essential for these effects.
• SlTFT1 stabilizes YFT1 by preventing its degradation by SlETP2-like3.

Conclusions:

• The SlTFT1-YFT1 complex is a novel genetic and molecular framework modulating tomato fruit ripening.
• SlTFT1 stabilizes YFT1, enhancing ethylene signaling and accelerating ripening.
• This study provides new insights into the regulation of ethylene signaling and fruit ripening in tomatoes.