SUN regulates vegetative and reproductive organ shape by changing cell division patterns

Area of Science:

• Plant genetics
• Developmental biology
• Agricultural science

Background:

• The SUN gene is a key regulator of fruit shape in tomato (Solanum lycopersicum).
• Understanding SUN's function is crucial for breeding tomatoes with desirable fruit morphology.

Purpose of the Study:

• To investigate the role of the SUN gene in tomato vegetative and reproductive development.
• To elucidate the molecular mechanisms by which SUN influences fruit shape.

Main Methods:

• Utilized near-isogenic lines (NILs) differing at the sun locus.
• Generated SUN overexpressors in wild and cultivated tomato backgrounds.
• Performed in situ hybridizations to determine SUN expression patterns.

Main Results:

• SUN controls tomato shape by increasing longitudinal and decreasing transverse cell division in fruits.
• SUN expression correlates with slender phenotypes in various organs and reduced seed weight.
• SUN overexpression results in more extreme phenotypes, including altered leaf and stem morphology and enhanced fruit elongation.

Conclusions:

• The SUN gene plays a significant role in regulating tomato fruit shape and influences multiple plant developmental processes.
• SUN's function extends beyond fruit development, impacting vegetative and reproductive organ morphology.