DELLA Protein RGA (RGA) Arabidopsis Thaliana Recombinant Protein

Member of the VHIID/DELLA regulatory family. Contains homopolymeric serine and threonine residues, a putative nuclear localization signal, leucine heptad repeats, and an LXXLL motif. Putative transcriptional regulator repressing the gibberellin response and integration of phytohormone signalling. DELLAs repress cell proliferation and expansion that drives plant growth. The protein undergoes degradation in response to GA via the 26S proteasome. RGA1 binds to PIF3 and inhibits its DNA binding activity and thus affects the expression of PIF3 regulated genes. RGA may be involved in reducing ROS accumulation in response to stress by up-regulating the transcription of superoxide dismutases. Represses GA-induced vegetative growth and floral initiation. Rapidly degraded in response to GA. Involved in fruit and flower development.

Probable transcriptional regulator that acts as a repressor of the gibberellin (GA) signaling pathway. Probably acts by participating in large multiprotein complexes that repress transcription of GA-inducible genes. Positively regulates XERICO expression in seeds. Upon GA application, it is degraded by the proteasome, allowing the GA signaling pathway. Compared to other DELLA proteins, it is the most sensitive to GA application. No effect of the BOI proteins on its stability. Its activity is probably regulated by other phytohormones such as auxin and ethylene, attenuation of auxin transport delaying its GA-induced degradation.