Molecular Genetics of Amino Acid Biosynthesis in Arabidopsis

Fink本研究将鉴定IAA生物合成途径中的特异性基因，这些基因的组织特异性，阻止表达的突变表型，以及影响该途径的调控突变。 植物激素吲哚乙酸（IAA）对植物生长和形态发生（例如顶端优势、细胞分裂、细胞扩大和侧根形成）具有显著不同的影响（22）。 我们相信，一旦克隆了特异参与IAA生物合成的基因，就可以理解内部IAA在这些过程中的作用。 由于该途径中的大多数结构基因存在多个拷贝，因此将在一组的每个成员中寻找突变，以便确定色氨酸/IAA途径中基因冗余的作用。 为了实现这一目标，设计了实验来改善转化、基因靶向和通过反义控制基因表达。 %%% 吲哚乙酸是一种影响植物生长和形态发生的植物激素。已知的大多数都是通过植物外部应用IAA来确定的。然而，很少有人知道它的合成和功能在体内的情况。芳香族氨基酸途径用于IAA的生物合成，我们将鉴定和克隆编码该途径酶的基因，确定基因拷贝数，并试图深入了解激素的内部功能。我们将在必要时开发实现这些目标所需的技术。 ***

Abstract Fink This proposal will identify the specific genes involved in pathway of IAA biosynthesis, the tissue specificity of these genes, the phenotypes of mutations that prevent expression, and regulatory mutations affecting the pathway. The plant hormone, indole acetic acid (IAA) has remarkably diverse effects on plant growth and morphogenesis (22) (e.g. apical dominance, cell division, cell enlargement and lateral root formation). Our belief is that once the gene(s) specifically involved in IAA biosynthesis are cloned, the role of internal IAA in each of these processes can be understood. As most of the structural genes in the pathway are found in multiple copies, mutations will be sought in each member of a set so that the role of gene redundancy in the tryptophan/IAA pathway can be determined. To achieve this goal experiments are designed to improve transformation, gene targeting, and the control of gene expression by antisense. %%% Indole acetic acid is a plant hormone which affects many growth and morphogenic characteristics of plants. Most of what is known have been determined by external application of IAA to plants. However, little is known about its synthesis and function in an in vivo situation. The aromatic amino acid pathway is utilized for the biosynthesis of IAA and we will identify and clone the genes encoding the enzymes of this pathway, determine gene copy number and attempt to gain insight into the internal functioning of the hormone. We will, as necessary, develop the technology needed to achieve these goals. ***