Evolution of carnivorous traps from planar leaves through simple shifts in gene expression

How do carnivorous plants get their amazing shapes?

We made this movie to illustrate our paper in Science Magazine.

Leaves vary from planar sheets and needle-like structures, to elaborate cup-shaped traps. Here we show that in the carnivorous plant Utricularia gibba, the upper leaf (adaxial) domain is restricted to a small region of the primordium which gives rise to the trap’s inner layer. This restriction is necessary for trap formation, as ectopic adaxial activity at early stages gives radialized leaves and no traps. We present a model that accounts for the formation of both planar and non-planar leaves through adaxial-abaxial domains of gene activity establishing a polarity field that orients growth. In combination with an orthogonal proximodistal polarity field, this system can generate diverse leaf forms, and can account for the multiple evolutionary origins of cup-shaped leaves through simple shifts in gene expression.

Movie credits: Movie credits Phil Robinson, Karen Lee and Jie Cheng, music is from Jazz suite 2 by Shostakovich.

Carnivorus plants,leaf development,plant science,science,biology,gene expression,evolution,evo devo,Utricularia gibba,Arabidopsis,Sarracenia,Optical Projection Tomography,Enrico Coen,