Functional characterization of the A. thaliana Aldehyde Dehydrogenase gene family

许多醛在低浓度下对生物体是有毒的。因此，重要的是严格控制代谢醛水平。乙醛脱氢酶（ALDH）是一个庞大的蛋白质家族，催化多种醛类底物的不可逆氧化。植物具有多种不同的ALDH，但关于其生物学作用的信息有限。本研究的目的是确定A.拟南芥的3类ALDH、BADH和turgor-responsive ALDH基因的成员，因为它们在渗透胁迫适应中的潜在作用。将采用以下实验方法：将分离所鉴定的ALDH基因的敲除突变，以研究其对生理和形态特征的影响。此外，将构建具有经修饰的ALDH基因表达的转基因植物。ALDH表达将在定义的生理条件下在野生型、突变体和转基因植物中进行分析。重组蛋白将用于确定ALDH的酶性质。为了确定推定的体内底物，野生型，突变体和转基因植物的代谢产物谱和底物捕获策略将在未来的方法中使用。

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.