A molecular framework for light and gibberellin control of cell elongation

Light and gibberellins (GA) regulate multiple aspects of plant development, and this paper is one of two studies that provide molecular insights into the connection between these pathways. Without GA, DELLA proteins (GA-signalling repressors) interact with PIFs (phytochrome-interacting proteins) and inhibit their binding to gene promoters. GA triggers degradation of DELLA proteins, thereby allowing PIFs to bind to their target promoters and regulate gene expression. These results reveal a signalling cascade that contributes to coordinated plant growth regulation by light and gibberellins.