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吲哚３甘油磷酸合酶（ＩＧＳ，ｉｎｄｏｌｅ３ｇｌｙｃｅｒｏｌｐｈｏｓｐｈａｔｅｓｙｎｔｈａｓｅ，ＥＣ４．１．１．４８）在色氨酸与吲哚乙酸的生物合成途径中，催化生成吲哚３甘油磷酸。研究该基因的表达调控，对于阐明高等植物是如何调控色氨酸及生长素合成是十分重要的。利用已克隆的ＩＧＳｃＤＮＡ，构建了谷胱甘肽转移酶（ＧＳＴ，ｇｌｕｔａｔｈｉｏｎｅＳｔｒａｎｓｆｅｒａｓｅ，ＥＣ２．５．１．１８）与吲哚３甘油磷酸合酶融合蛋白的表达质粒，并将其导入到在异丙基βＤ硫代半乳糖苷（ＩＰＴＧ）诱导下能高效表达的ＩＧＳ基因缺陷菌株ｔｒｐＣ９８００λＫＣ大肠杆菌中。高表达的融合蛋白通过谷胱甘肽琼脂糖（ｇｌｕｔａｔｈｉｏｎｅａｇａｒｏｓｅ）亲和层析和ＳＤＳ聚丙烯酰胺凝胶电泳纯化后，用以免疫兔子制备抗血清。免疫印迹法分析表明拟南芥（Ａｒａｂｉｄｏｐｓｉｓｔｈａｌｉａｎａ（Ｌ．）Ｈｅｙｎｈ．）四种常用生态型只合成一种分子量约为４０ｋＤ的吲哚３甘油磷酸合酶蛋白。在Ａｇ＋、紫外线等逆境条件下，ＩＧＳ含量都有较大幅度的增加，这说明ＩＧＳ可能与植物的防御反应紧密相关。
Indole 3 glycerophosphate synthase (IGS, indole 3 glycerolphosphatesynthase, EC4.1.1.48) in the tryptophan and indole acetic acid biosynthetic pathway, the catalytic generation of indole 3 glycerophosphate. To study the expression and regulation of this gene is very important for elucidating how higher plants regulate the synthesis of tryptophan and auxin. Using the cloned IGScDNA, an expression plasmid of glutathione S-transferase (EC2.5.1.18) and indole-3-glycerophosphate synthase fusion protein was constructed and introduced into IGS gene-deficient strain trpC9800 λKC highly expressed in E. coli induced by isopropyl-β-D-thiogalactoside (IPTG). The highly expressed fusion protein was purified by glutathione-agarose affinity chromatography and SDS-polyacrylamide gel electrophoresis to immunize rabbits to prepare antisera. Western blot analysis showed that Arabidopsis (Arabidopsisthaliana (L.) Heynh.) Four commonly used ecological type synthesis of only a molecular weight of about 40kD indole 3 glycerophosphate synthase protein. Under the conditions of Ag + and ultraviolet light, the content of IGS increased greatly, which indicated that IGS may be closely related to plant defense response.