From flower to fruit: a game of internal tensions

Contrairement à une cellule animale, une cellule végétale ne peut ni ramper ni se déplacer: elle est emprisonnée dans une paroi rigide, collée à ses voisines pour la vie. Une cellule née au centre d'un jeune fruit s'y trouvera encore quand ce fruit sera mûr.

Therefore, when two tissues fused together are programmed to grow at different rates, neither can simply move apart, something has to give. The fast fabric puts the other under tension; the slow fabric, in turn, slows it down.

A study led by a research team from the University of Montreal shows that this “tightness”, far from being a simple inconvenience, is one of the tools that the plant uses to form its fruit.

The work, carried out by doctoral student Binghan Wang under the direction of Daniel Kierzkowski, professor in the Department of Biological Sciences at UdeM and researcher at the Plant Biology Research Institute, combines time-lapse imaging, microsurgery, genetics and computer modeling, the latter technique having been developed in collaboration with Richard Smith of the John Innes Center (United Kingdom).

Why the ladies' arabette? 

The team studiedArabidopsis thalianaor lady's cress, a small plant that biologists have used as a reference model for decades: short life cycle, well-known and fully sequenced genome and large genetic toolbox allowing easy creation of mutants to test a hypothesis. Discoveries about it generally shed light on mechanisms shared by many other plants, such as those in the brassica family, which includes canola, cabbage, broccoli, etc.