Image of the Day: Tomato Domestication

Scientists identify a transcription factor that plays a key role in increased fruit size.

Amy Schleunes
Amy Schleunes

A former intern at The Scientist, Amy studied neurobiology at Cornell University and later earned her MFA in creative writing from the University of Iowa. She is a Los...

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Changes in tomato fruit size over the course of domestication: A) wild ancestor Solanum pimpinellifolium; B) semi-domesticated S. lycopersicum variety cerasiforme; C-F) domesticated Solanum lycopersicum varieties: D) lc mutant; E) lc and fas mutant; and F) ENO mutant
Fernando J. Yuste-Lisbona, Sandra Bretones, and Rafael Lozano

Amutation in the newly identified tomato fruit transcription factor EXCESSIVE NUMBER OF FLORAL ORGANS (ENO) promotes larger flowers and fruit in cultivated tomatoes, according to a study published on March 16 in PNAS.

ENO regulates the activity of a gene that maintains floral stem-cell homeostasis in the meristem, a region near the tips of the roots and shoots of plants that is rich in undifferentiated cells, the authors report in the paper, and a variant in the ENO promoter that was selected for during the domestication of tomatoes has resulted in the large fruits we recognize today.

Wild type flower (left) and ENO mutant flower (right)
Fernando J. Yuste-Lisbona, Antonia Fernández-Lozano, and Rafael Lozano

F.J. Yuste-Lisbona et al., “ENO regulates tomato fruit size through the floral meristem development network,” PNAS, doi:10.1073/pnas.1913688117, 2020.