Root branching plays a critical role in the definition of root system architecture and plants adaptation to their environment. Root branching consists in the positioning, formation and emergence of lateral roots (LR). LRs develop from a limited pool of pericycle cells in inner tissues of the mature root which divide to form a lateral root primordium (LRP) that is gradually organized into a root apical meristem.

Previous studies have identified many genetic and hormonal factors involved in the regulation of LR patterning processes. However, how these components interact to form a network that successfully controls the organisation of a new functional meristem is currently poorly understood.

We recently showed that the LRP organization is not controlled by a stereotyped cell division pattern suggesting that patterning of cell identities depends on the dynamic interaction between an emergent organizing center and the genetic network existing within the proliferating cells. To follow up on this study, we initiated a systems biology approach to identify and study the global gene regulatory network (GRN) governing LR formation in the model plant Arabidopsis thaliana.