FLORAL MERISTEMS TO FLORAL ORGANS - GENES-CONTROLLING EARLY EVENTS IN ARABIDOPSIS FLOWER DEVELOPMENT

Molecular and genetic studies show that the underlying mechanisms controlling flower development are largely conserved in distantly related dicotyledonous plant species. These studies have identified early-acting genes that promote the formation of floral meristems and later-acting genes that determine the fate of floral organ primordia. The floral meristem identity genes lie at the top of a regulatory hierarchy that leads to the activation of the organ identity genes. Subsequent regulatory interactions between the organ identity genes restrict their domains of activity. The resulting spatial domains of gene activity allow cells within the floral meristem to assess their position and, hence, to differentiate into the appropriate organ type.