Abstract

Plants are expert architects that control cell proliferation and differentiation with exquisite spatiotemporal resolution to produce a diversity of shapes and forms. The colourful patterns on the petals of flowering plants perfectly illustrate their engineering skills. These patterns are also functionally relevant: they can protect pollen grains from UV radiation and act as communication devices to attract pollinators. Petal patterns are often highly elaborated and combine differences in pigmentation, cell shape and texture to generate neighbouring tissues with distinct appearances. However, the mechanisms used to program cell behaviour in a coordinated fashion across the epidermis of a developing petal are not well understood. I will present some results our group obtained while investigating pattern formation and evolution across a small group of Hibiscus species. Our results help us understand how plants can set-up boundaries within the petal epidermis and how evolution tinkers with these processes to generate the diversity of patterns observed in nature.