Szerszen J B, Szczyglowski K, Bandurski R S
Department of Botany and Plant Pathology, Michigan State University, East Lansing 48824.
Science. 1994 Sep 16;265(5179):1699-701. doi: 10.1126/science.8085154.
Plants contain most of the growth hormone indole-3-acetic acid (IAA) in conjugated forms believed to be inactive in promoting growth. The iaglu gene, which controls the first step in the biosynthesis of the IAA conjugates of Zea mays, encodes (uridine 5'-diphosphate-glucose:indol-3-ylacetyl)-beta-D-glucosyl transferase. Protein synthesized by Escherichia coli that contained cloned 1-O-beta-D-indol-3-ylacetyl-glucose complementary DNA (cDNA) was catalytically active. The predicted amino acid sequence of the cDNA was confirmed by amino-terminal sequencing of the purified enzyme. Homologous nucleotide sequences were found in all plants tested. The blockage or enhancement of iaglu expression may permit regulation of plant growth.
植物中大部分生长激素吲哚 - 3 - 乙酸（IAA）以共轭形式存在，据信这种形式在促进生长方面没有活性。iaglu基因控制着玉米IAA共轭物生物合成的第一步，它编码（尿苷5'-二磷酸葡萄糖：吲哚 - 3 - 基乙酰基）-β-D - 葡萄糖基转移酶。含有克隆的1 - O - β - D - 吲哚 - 3 - 基乙酰基 - 葡萄糖互补DNA（cDNA）的大肠杆菌合成的蛋白质具有催化活性。通过对纯化酶的氨基末端测序证实了cDNA预测的氨基酸序列。在所有测试的植物中都发现了同源核苷酸序列。iaglu表达的阻断或增强可能有助于调节植物生长。
