A DELLAcate balance: the role of gibberellin in plant morphogenesis

The importance of gibberellin (GA) in vegetative and reproductive development has been known for some time. Recent studies have uncovered new roles of GA in leaf differentiation, photomorphogenesis and pollen-tube growth. Significant contributions to our understanding of GA-regulated morphogenesis include the identification of upstream regulators of GA biosynthesis, the elucidation of the function of GA signaling components, and the isolation of downstream targets. In addition, the mechanisms of interactions between GA and other hormone pathways are beginning to be revealed at the molecular level.