Plant boundary zones initiate development of new meristems

Boundary zones were previously seen as physical barriers that separate plant tissues and thus allow the development of functional organs. However, recent studies revealed that boundaries, like those between the shoot apical meristem and leaf primordia and those between leaflets, also serve as launching pads for secondary meristem formation and play an important role in determining plant architecture. Interestingly, establishment of boundary zones during shoot branching and complex leaf development is regulated by homologous genes.