A SlERF4-SlTPP1 module enhances drought tolerance in tomato by increasing the root/shoot ratio

Area of Science:

• Plant Biology
• Genetics
• Agricultural Science

Background:

• Drought tolerance is crucial for crop improvement.
• Root/shoot ratio (R/S) is a key plant adaptation to drought.
• Trehalose-6-phosphate phosphatase (TPP) genes' role in R/S regulation is unknown.

Purpose of the Study:

• Characterize SlTPP1's role in tomato drought tolerance.
• Investigate the regulatory mechanism of SlTPP1 in response to drought.
• Identify upstream regulators of SlTPP1.

Main Methods:

• Gene expression analysis under drought stress.
• CRISPR/Cas9 gene editing.
• Promoter binding assays.
• Physiological measurements of tomato plants.

Main Results:

• SlTPP1 expression is induced in roots and suppressed in leaves by drought.
• SlTPP1 overexpression promotes root growth and increases R/S.
• SlERF4 directly represses SlTPP1 transcription.
• SlERF4 knockout enhances drought tolerance and R/S.

Conclusions:

• A novel SlERF4-SlTPP1 regulatory module enhances tomato drought tolerance.
• This module regulates R/S by modulating root growth and leaf ethylene signaling.
• Provides targets for breeding drought-tolerant tomato varieties.