Study on gibberellin perception

我们分析了与GA结合的水稻GA受体（OsGID 1）的三维结构。整体结构显示出与HSL相似的α/β-水解酶折叠。GA结合口袋对应于HSL的底物结合位点。在OsGID 1结构的基础上，我们对GA结合的重要残基进行了诱变，并检测了它们的结合活性。几乎所有的它们都显示出非常少的活性或没有活性，证实了通过结构分析揭示的残基对于GA结合是重要的。这些结果表明，GID 1起源于HSL，并通过适应植物进化过程中参与GA结合的氨基酸而进一步修饰，从而对生物活性GA具有更高的亲和力和更严格的选择性。

We analyzed the 3D structure of rice GA receptor (OsGID1) bound with GA. The overall structure shows an α/β-hydrolase fold similar to that of HSLs. The GA-binding pocket corresponds to the substrate-binding site of HSLs. On the basis of the OsGID1 structure, we mutagenized important residues for GA binding and examined their binding activities. Almost all of them showed very little or no activity, confirming that the residues revealed by structural analysis are important for GA binding. The observations indicate that GID1 originated from HSL and was further modified to have higher affinity and more strict selectivity for bioactive GAs by adapting the amino acids involved in GA binding in the course of plant evolution.