Molecular mechanisms and roles of the mammalian 2-oxoglutarate-dependent oxygenases AlkBH1 and AlkBH7

哺乳动物 2-氧化戊二酸依赖性加氧酶 AlkBH1 和 AlkBH7 的分子机制和作用

• 批准号: 442081128
• 负责人: Dr. Sabine Schneider
• 金额: --
• 依托单位: Department Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/442081128?language=en
• 关键词: Molecular; mechanisms; roles; mammalian; oxoglutarate

Independent from the DNA genetic code, gene and protein activity is controlled by epigenetic mechanisms through writing, reading and erasing specific epigenetic marks. These marks include the covalent modifications of histones, DNA and RNA with methyl groups. These methyl groups play an essential role in many cellular processes. Responsible for the spacial and temporal maintenance of these epigenetic marks is carried out by so called "writer" and "eraser" enzymes. Here enzymes belonging to the Fe2+- and 2-oxoglutarate (2OG; = α-ketoglutarate) dependent oxygenase family are particular prominent actors. About 70 members of the Fe(II)/2OG-family across all kingdoms of life are known to date. These enzymes use the cosubstrate 2OG to bind to ferrous iron and to activate molecular oxygen in order to catalyse the transfer of the molecular oxygen onto a methyl group, resulting either in a stable hydroxylated product (=hydroxylases) or demethylation of the substrate via oxidative demethylation (=demethylases). The subfamily this proposal addresses are the AlkB-homologs (AlkBHs), which are found in various organisms such as Escherichia coli, Drosophila melanogaster, Schizosaccharomyces pombe, Cenorhabditis elegans and mammals.In mammals there are nine AlkB-homologs known by now: AlkBH1-8 and the fat mass- and obesity-associated gene product (FTO). The differences in sequence, structural elements and accessory domains account for their remarkably large diversity in substrates and biological roles. For individual mammalian AlkBHs it was shown, that loss-off function as well as their aberrant expression and activities can be linked to various diseases phenotypes, such as obesity, severe sensitivity to inflammation, multiple malformations, infertility and cancer, which emphasizes the importance of these enzymes. However, a direct link between the molecular functions, observed phenotype and the substrate scope for many of the human AlkBHs is still unclear. In the here proposed research project our aim is to elucidate the molecular mechanism of the most elusive human AlkBHs. We want to learn about their substrates and interaction network. Our focus will be the human AlkBH1 and AlkBH7 proteins. The employed methods involve cell biology, mass spectrometry and structural biology.

基因和蛋白质的活性独立于DNA遗传密码，由表观遗传机制通过写入、读取和擦除特定的表观遗传标记来控制。这些标记包括组蛋白、DNA 和 RNA 与甲基的共价修饰。这些甲基在许多细胞过程中发挥着重要作用。负责这些表观遗传标记的空间和时间维护的是所谓的“写入”和“擦除”酶。在此，属于 Fe2+- 和 2-酮戊二酸 (2OG；= α-酮戊二酸) 依赖性加氧酶家族的酶是特别重要的参与者。迄今为止，已知生命王国中约有 70 个 Fe(II)/2OG 家族成员。这些酶使用共底物 2OG 与亚铁结合并激活分子氧，以催化分子氧转移到甲基上，从而产生稳定的羟基化产物（=羟化酶）或通过氧化去甲基化（=去甲基酶）对底物进行去甲基化。该提案涉及的亚家族是 AlkB 同源物 (AlkBH)，在多种生物体中都有发现，例如大肠杆菌、黑腹果蝇、粟酒裂殖酵母、秀丽隐杆线虫和哺乳动物。在哺乳动物中，目前已知有九种 AlkB 同源物：AlkBH1-8 以及与脂肪量和肥胖相关的 基因产物（FTO）。序列、结构元件和辅助结构域的差异导致它们在底物和生物学作用方面具有显着的多样性。对于个体哺乳动物 AlkBH，研究表明，功能丧失及其异常表达和活性可能与多种疾病表型有关，例如肥胖、对炎症严重敏感、多种畸形、不孕症和癌症，这强调了这些酶的重要性。然而，许多人类 AlkBH 的分子功能、观察到的表型和底物范围之间的直接联系仍不清楚。在此提出的研究项目中，我们的目标是阐明最难以捉摸的人类 AlkBH 的分子机制。我们想了解它们的底物和相互作用网络。我们的重点是人类 AlkBH1 和 AlkBH7 蛋白。所采用的方法涉及细胞生物学、质谱法和结构生物学。