Research focus

​The root system is fundamental for plant development, is crucial for overall plant growth and  is recently being recognized as the key for future crop productivity improvement.
A major determinant of root system architecture is root branching or the initiation of lateral roots. During root branching renewing mitotic activity in lateral root founder cells is required, however, not sufficient. What is more, lateral root founder cells have to be instructed to undergo formative or asymmetric divisions rather than performing the default proliferative divisions. How organisms can switch from proliferative cell division activity to a formative cell division mode is a central but still unanswered question in biology. The inducibility of the lateral root initiation process by application of plant growth regulators provides an elegant experimental system to tackle this problem.
In Arabidopsis, and most likely in a plethora of plants, the lateral roots are initiated by local activation of pericycle founder cells at the xylem poles. To date, the signaling cascade towards the specification of the lateral root founder cells and the asymmetric divisions is not elucidated, and represents the major theme of our current research. Various independent but complementary transcript profiling studies have been performed using a lateral root inducible system both in Arabidopsis and in maize. Based on the global changes in the transcriptome during the initial phase of lateral root induction, functional analyses of potential key-regulators for root branching are currently being analyzed and put in a molecular model for root branching that is gradually gaining resolution. This molecular framework is used to design strategies to alter/improve crop root systems and will be essential to understand the reaction and adaptation of plants to adverse environmental conditions.