赤霉素是一种重要的植物激素，调控几个发育过程。赤霉素与其受体GID1的结合，导致DELLA家族的转录调控因子的识别，这些调控因子抑制赤霉素信号作用。
现在，两个小组发表了来自两种不同植物物种的赤霉素受体的晶体结构。Murase等人确定了与GID1和来自拟南芥的一个DELLA蛋白碎片相结合的赤霉素的一种三元复合物的结构。Shimada等人对与水稻GID1相结合的赤霉素进行了研究。这些结构揭示了一个受体识别机制，该机制与生长素的识别机制截然不同。关于受体结构的详细知识，有可能帮助设计用于农业生产的更为有效或更为便宜的生长调控因子。（生物谷Bioon.com）
生物谷推荐原始出处：
Nature 456, 459-463 (27 November 2008) | doi:10.1038/nature07519
Gibberellin-induced DELLA recognition by the gibberellin receptor GID1
Kohji Murase1,2,3, Yoshinori Hirano1,3, Tai-ping Sun2 & Toshio Hakoshima1
1 Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
2 Department of Biology, Duke University, Durham, North Carolina 27708, USA
3 These authors contributed equally to this work.
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.
