Gibberellin-induced DELLA recognition by the gibberellin receptor GID1.
Gibberellins control a range of growth and developmental processes in higher plants and have been widely used in the agricultural industry. By binding to a nuclear receptor, GIBBERELLIN INSENSITIVE DWARF1 (GID1), gibberellins regulate gene expression by promoting degradation of the transcriptional regulator DELLA proteins, including GIBBERELLIN INSENSITIVE (GAI). The precise manner in which GID1 discriminates and becomes activated by bioactive gibberellins for specific binding to DELLA proteins remains unclear. Here we present the crystal structure of a ternary complex of Arabidopsis thaliana GID1A, a bioactive gibberellin and the amino-terminal DELLA domain of GAI. In this complex, GID1A occludes gibberellin in a deep binding pocket covered by its N-terminal helical switch region, which in turn interacts with the DELLA domain containing DELLA, VHYNP and LExLE motifs. Our results establish a structural model of a plant hormone receptor that is distinct from the mechanism of the hormone perception and effector recognition of the known auxin receptors.
Murase
Kohji
K
Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
Hirano
Yoshinori
Y
Sun
Tai-ping
TP
Hakoshima
Toshio
T
D020816:Amino Acid Motifs; D017360:Arabidopsis / Q000737:chemistry* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002942:Circular Dichroism; D018360:Crystallography, X-Ray; D005875:Gibberellins / Q000378:metabolism / Q000494:pharmacology*; D008954:Models, Biological; D008958:Models, Molecular; D010937:Plant Growth Regulators / Q000378:metabolism / Q000494:pharmacology*; D011485:Protein Binding; D017434:Protein Structure, Tertiary / Q000187:drug effects; D011956:Receptors, Cell Surface / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity
D029681:Arabidopsis Proteins; C109555:GAI protein, Arabidopsis; C512225:GID1a protein, Arabidopsis; D005875:Gibberellins; D010937:Plant Growth Regulators; D011956:Receptors, Cell Surface