Cutinsomes and CUTIN SYNTHASE1 Function Sequentially in Tomato Fruit Cutin Deposition

Area of Science:

• Plant biology
• Biochemistry
• Developmental biology

Background:

• Plant aerial organs are protected by a cuticle, primarily composed of the polyester cutin.
• Cutin deposition is essential for plant protection and development.

Purpose of the Study:

• To investigate the mechanisms of cutin synthesis and deposition in tomato fruit.
• To understand the roles of cutinsomes and CUTIN SYNTHASE1 (CUS1) in cuticle formation.

Main Methods:

• Analysis of cutin deposition mechanisms in *Solanum lycopersicum* fruit.
• Correlation of deposition with organ growth, cell division, and cell expansion phases.

Main Results:

• Two distinct cutin deposition mechanisms identified, temporally coordinated with plant growth.
• Cutinsomes facilitate procuticle synthesis during cell division.
• CUTIN SYNTHASE1 (CUS1) drives massive cuticle deposition during cell expansion.

Conclusions:

• Cutin synthesis and deposition involve a complex interplay with cell wall development and epidermal cell size.
• CUS1 influences coordinated growth of epidermal wall domains and affects cell size.