Plants have a particular need for strict regulation of cell division orientation, as plant cells are unable to move due to the presence of a rigid cell wall. Two types of division can be distinguished: Anticlinal divisions (AD) occur perpendicular to the tissue growth axis, generate more cells within
one layer and generally allow for longitudinal growth; Periclinal divisions (PD), on the other hand, occur parallel to the growth axis of the tissue, generate additional cell layers and are responsible for radial growth. A tissue that is very capable of PD, is vascular tissue. This tissue is needed for
transport of water and nutrients and for providing mechanical support. Vascular tissue is also the main component of wood in trees, which makes it an economically important tissue to study. Despite its importance for plant development in general, it is currently unknown how a cell makes
the decision to divide one way or the other. In this project, I will study this process, using a pathway that was recently identified to control the switch between AD and PD in vascular cells, the TMO5/LHW pathway. Using a novel approach, I aim to find upstream regulators of the TMO5/LHW pathway, by setting up a high throughput screening system and characterize their role
during vascular developement. This will help to sketch a comprehensive picture of how this pathway controls the orientation of cell division in plants.