[中国农业大学CAU 植物生理 期末]第二节 生长素.pptxVIP

第二节 生长素;预习提问1;预习提问2;预习提问3;一、生长素的化学结构 Chemical Structure of Auxin;吲哚-3-乙酸（IAA）;20:47;Orange agent;20:47;生长素的构效关系;生长素分子结构特征的生化本质 ;a, A close-up view of the auxin-binding site with its nearby InsP6?molecule. The auxin molecule (IAA) is shown as a green stick model, together with its positive?Fo?-?Fc?electron density calculated and contoured at 3?before it was built into the complex model. The TIR1 residues surrounding auxin and right underneath the auxin-binding site are shown as a yellow stick model. A central water molecule as part of the pocket floor is shown as a red sphere. The hydrogen-bond and salt-bridge network connecting auxin and InsP6?are indicated by orange dashed lines.?b, A slab view of the TIR1 cavity accommodating the auxin indole ring. The TIR1-LRR domain is in surface representation. Three layers of TIR1 residues defining a wall for the auxin-binding site are modelled as sticks. Arg?403 interacts with the auxin carboxyl group and is coloured blue.?c, GST pull-down assay with (+) or without (-) 50?M 1-NAA. In the upper panel, purified recombinant wild type (WT) or mutants GST–TIR1 are visualized by Coomassie staining for loading control. In the lower panel, Flag-tagged IAA7 pulled down by GST–TIR1 was detected by western blot.?d, A top view of the TIR1 cavity with IAA, 1-NAA and 2,4-D bound. The three auxin analogues are all shown as green stick models. In each panel, two black arrows indicate the widest dimension of each compound. ;20:47;二、生长素的生物合成和代谢Auxin Biosynthesis metabolism;Site of Auxin biosynthesis;16;生长素的生物合成途径（一） —色氨酸依赖途径;20:47;20:47;20:47;Concentrations of IAA in different regions of the shoot of a wild-type and transformant tobacco plant. The bars at the different regions indicate the auxin concentrations found in leaves and stems ;生长素生物合成途径—非色氨酸依赖途径;Tryptophan /Auxin biosynthetic pathway;吲哚-3-丁酸（IBA）的生物合成;生长素的代谢Metabolism of Auxin;Most auxin in plants is in a covalently bound form;27;20:47;Factors regulating the steady-state lev