BIOCHEMISTRY/BIOLOGY OF 5-LIPOXYGENASE AND LEUKOTRIENES

5-脂加氧酶和白三烯的生物化学/生物学

• 批准号: 2735381
• 负责人: COLIN D. FUNK
• 金额: $ 27.8万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-07-10 至 2000-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2735381
• 关键词: adenosine triphosphate; affinity labeling; asthma; cofactor; disease /disorder model; enzyme mechanism; enzyme structure; inflammation; intermolecular interaction; intracellular transport; laboratory mouse; leukotrienes; lipoxygenase; mast cell; phosphorylation; protein transport; site directed mutagenesis; tissue /cell culture

DESCRIPTION: Leukotrienes are potent lipid mediators, generated by the enzyme 5-lipoxygenase (5LO), and released from inflammatory mast cells, eosinophils and macrophages. There is good evidence to support the role of leukotrienes in the proinflammatory events and pathogenesis of asthma, a common, chronic disorder which afflicts nearly ten percent of the U.S. population. In light of recent data showing the presence of this enzyme in the nucleus of certain inflammatory cells, associated with euchromatin, which are areas of active gene transcription, one hypothesis to be explored in this proposal is that there are novel, leukotriene-independent functions of this protein in the nucleus. An integrated plan will be implemented to define further the biochemistry and biology of 5LO and leukotrienes. In Specific Aim 1, the ATP-binding domain of 5LO will be characterized by photoaffinity labeling and in vitro site-directed mutagenesis experiments in an effort to understand better the functional importance of the ATP cofactor. In Specific Aim 2, the signals directing 5LO to the nucleus, the specific sites of translocation, and interaction with DNA will be studied in mast cells. The role of 5LO in transcriptional regulation, and phosphorylation status of the protein in IgE/antigen-activated cells will be examined. In Specific Aim 3, the role of 5LO products in the development of airways hyperresponsiveness and the immune response will be investigated in mice with a targeted disruption of the 5LO gene using an allergic airway inflammation model that displays the hallmark traits of asthma. Since both of these parameters were significantly diminished in 5LO deficient mice in initial studies, a focus in this proposal will be reconstitution of the responses via bone marrow-derived precursor cells containing 5LO and recombinant adenoviral delivery. These studies should provide a means to elucidate the important leukotriene-dependent and independent functions of 5LO in allergic inflammation and inflammatory cells, as well as bring to light the interaction of ATP with 5LO.

描述：白细胞是有效的脂质介质，由 酶5-氧化酶（5LO），并从炎性肥大细胞中释放， 嗜酸性粒细胞和巨噬细胞。 有充分的证据支持 哮喘的促炎事件和发病机理中的白细胞 常见的慢性疾病，遭受了美国近十％的痛苦 人口。 鉴于最新数据显示了这种酶在 某些炎症细胞的核，与白染色质有关， 是活性基因转录的领域，要探讨一个假设 在此提案中，有新颖的，白细胞独立的功能 该核中的该蛋白质的蛋白质。 一项集成计划将被实施 进一步定义5LO和白三烯的生物化学和生物学。 在 特定的目标1，5LO的ATP结合域将以特征为特征 光性标记和体外位置定向的诱变实验 努力更好地了解ATP的功能重要性 辅因子。 在特定的目标2中，信号将5lo引向核， 特定的易位部位以及与DNA的相互作用将在 肥大细胞。 5lo在转录调节中的作用，以及 IgE/抗原激活细胞中蛋白质的磷酸化状态将是 检查。 在特定的目标3中，5lo产品在开发中的作用 气道高反应性和免疫反应将在 使用过敏性气道有针对性破坏5LO基因的小鼠 炎症模型显示出哮喘的标志性特征。 两者既是 这些参数中的5LO缺陷小鼠在 初步研究，该提案的重点将是重构 通过骨髓衍生的前体细胞的反应，该细胞包含5lo和 重组腺病毒输送。 这些研究应提供一种阐明重要的方法 5LO在过敏性中依赖于5LO的白三烯依赖性和独立功能 炎症和炎症细胞，并揭示 ATP与5LO的相互作用。