Multispecies transcriptomes reveal core fruit development genes.

Area of Science:

• Plant Biology
• Evolutionary Developmental Biology
• Genomics

Background:

• Angiosperm evolution features recurrent transitions from dry to fleshy fruits, impacting ecology and economics.
• Domestication further modifies fruit phenotypes through artificial selection, yet the molecular underpinnings are not fully understood.

Purpose of the Study:

• To investigate conserved and divergent gene expression patterns during fruit development and evolution.
• To identify molecular factors underlying the transition from dry to fleshy fruits and the effects of domestication.

Main Methods:

• RNA sequencing (RNA-seq) of pericarp tissue from desert tobacco, wild and cultivated tomato, Arabidopsis, and melon.
• Application of novel bioinformatic methods to analyze gene expression across dry/fleshy and wild/domesticated fruit types.

Main Results:

• A conserved set of 121 core orthologous genes exhibits common expression patterns across all five species, involved in cell division, cell wall biosynthesis, and developmental patterning.
• Accessory genes show conserved expression within fruit types but not among them, highlighting differences between dry and fleshy fruits.
• Striking conservation of gene expression patterns was observed despite significant evolutionary distances and phenotypic shifts.

Conclusions:

• A small subset of core fruit development genes plays a conserved role across diverse angiosperms.
• Gene expression patterns reveal conserved mechanisms underlying fruit development and evolution, even with dramatic phenotypic divergence.