Figure 2. A model for gibberellin (GA) signaling in Arabidopsis. In the absence of GAs, DELLA proteins accumulate in cell nucleus and inhibit GA responses. In the presence of GA signal, the GA receptor GID1 binds the hormone and undergoes a conformational change suitable for DELLAs binding. The resulting GA-GID1-DELLA complex triggers degradation of DELLAs via the 26S proteasome pathway, resulting in release of DELLA-repressed plant growth.