Scientists from VIB and Ghent University under the guidance of Prof. Dr. Jenny Russinova have uncovered a novel mechanism in plants that controls an important decision step in stomatal lineage to divide asymmetrically or to differentiate. This is a decisive step for the formation of stomata, tiny pores on the plant surface, produced by asymmetric cell division. In the model plant Arabidopsis thaliana, they identified a scaffolding protein, POLAR, and demonstrated that POLAR brings a subset of GSK3-like kinases to their interacting partners at the polarized end of the stomatal precursor cell to initiate asymmetric cell division. This surprising regulation through scaffolding might be a more common mechanism to control GSK3-like kinases functions in plants.