Functional characterization of the A. thaliana Aldehyde Dehydrogenase gene family

许多醛在低浓度时对生物体是有毒的。因此，严格控制代谢醛水平是很重要的。乙醛脱氢酶(ALDHs)是一个蛋白质家族，催化多种醛底物的不可逆氧化。植物具有多种不同的ALDH，但关于它们的生物学作用的信息有限。本研究的目的是确定拟南芥ALDH基因家族的生物学功能，重点研究ALDH、BADH和膨压反应ALDH基因家族的成员，因为它们在渗透胁迫适应中具有潜在的作用。将采取以下实验方法：分离已鉴定的ALDH基因的敲除突变，以研究它们对生理和形态特征的影响。此外，还将构建表达ALDH基因修饰的转基因植株。ALDH在野生型、突变型和转基因植物中的表达将在特定的生理条件下进行分析。重组蛋白将用于确定ALDHs的酶性质。为了确定可能的体内底物，未来的方法将使用野生型、突变型和转基因植物的代谢物分析和底物捕获策略。

Many aldehydes are toxic for organisms at low concentrations. It is therefore important that metabolic aldehyde levels are strictly controlled. Aldehyde dehydrogenases (ALDHs) form a large protein family and catalyze the irreversible oxidation of a wide range of aldehyde substrates. Plants possess a variety of distinct ALDHs, but information on their biological role is limited. The aim of the proposed research project is to determine the biological function of the ALDH gene family from A. thaliana focusing on members of the class-3 ALDH, BADH and turgor-responsive ALDH genes, because of their potential role in osmotic stress adaptation. The following experimental approaches will be pursued: Knock-Out mutations for the identified ALDH genes will be isolated to study their effects on physiological and morphological characteristics. In addition, transgenic plants with a modified ALDH gene expression will be constructed. ALDH expression will be analyzed in wild-type, mutant and transgenic plants under defined physiological conditions. Recombinant proteins will be used to determine enzymatic properties of the ALDHs. To identify putative in vivo substrates, metabolite profiling of wild-type, mutant and transgenic plants and a substrate trapping strategy will be used in future approaches.