Structural and Functional Analysis of Cardiolipin-Associated Bax

心磷脂相关 Bax 的结构和功能分析

• 批准号: 7656755
• 负责人: JUANITA C SHARPE
• 金额: $ 17.68万
• 依托单位: CHICAGO STATE UNIVERSITY
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7656755
• 关键词: Affect; Apoptosis; Apoptotic; Area; BH3 Domain; Behavior; Binding; C-terminal; Cardiolipins; Cell Count; Cell Death; Cells; Cessation of life; Cytochromes; Data; Development; Disease; Disruption; Environment; Event; Family member; Funding; Goals; Grant; Helix (Snails); Human; Investigation; Length; Light; Lipid Binding; Lipids; Malignant Neoplasms; Measures; Mediating; Membrane; Membrane Proteins; Methods; Mitochondria; Modeling; Molecular Conformation; Mutate; Mutation; Neurodegenerative Disorders; Numbers; Pathologic; Penetration; Peptides; Physiological; Process; Progress Reports; Protein Family; Proteins; Purpose; Recombinants; Regulation; Reproduction; Research; Role; Signal Transduction; Spectrum Analysis; Spin Labels; Stroke; Structure-Activity Relationship; Techniques; Thinking; Work; base; cancer cell; cell injury; cytochrome c; defined contribution; dimer; ear helix; interest; member; membrane activity; membrane model; mitochondrial membrane; mutant; novel; prevent; reconstitution; size

Cancer arises as a result of the inability of damaged cells to initiate a signaling cascade that results in the destruction of the cell and clearance from the body. This process, known as apoptosis, is necessary to prevent reproduction of damaged cells that leads to cancer. A family of proteins known as the Bcl-2 protein family regulates apoptosis. The Bcl-2 protein family works to promote cell death through the interaction of death promoting proteins. Bax, a pro-apoptotic member of this family, initiates the cell death cascade by releasing cytochrome C. Bax has the ability to mediate cytochrome c release by working in conjunction with cardiolipin. Previous studies have shown that the presence of cardiolipin enhances the ability of Bax to form pores in reconstituted membranes through an, as yet, unknown mechanism. Preliminary data from our lab has begun to elucidate the mechanism of interaction between Bax and cardiolipin. In the presence of cardiolipin Bax undergoes a unique conformational change that facilitates the release of molecules from model membranes. The goals of the current project are to determine the impact that this conformational change has on the active and functional conformation of Bax. Our goals are to detail the structural changes and to correlate these changes with the function of Bax at the membrane. This will be achieved by studying pore formation and oligomerization of membrane-associated Bax using fluorescent spectroscopic techniques. We will also study how regions of Bax contribute to membrane recognition pore formation and oligomerization through the use of mutants. The two regions of Bax that are of interest are the BH3 domain, also called the putative cardiolipin binding region, and the c-terminal hydrophobic domain. Understanding the mechanisms of pore formation and oligomerization as well as how domains of Bax contribute to the membrane-active conformation will enhance our understanding of apoptosis and aid in our ability to overcome the barriers that cancer cells erect to evade apoptosis.

癌症的发生是由于受损细胞无法启动信号级联反应，从而导致 细胞的破坏和从体内的清除。这个过程称为细胞凋亡，对于 防止导致癌症的受损细胞的繁殖。称为 Bcl-2 蛋白的蛋白质家族 家族调节细胞凋亡。 Bcl-2 蛋白家族通过以下相互作用促进细胞死亡： 促进死亡的蛋白质。 Bax 是该家族的促凋亡成员，通过以下方式启动细胞死亡级联： 释放细胞色素 C。Bax 能够通过与 心磷脂。先前的研究表明，心磷脂的存在增强了 Bax 形成的能力 通过迄今为止未知的机制在重组膜中形成孔。我们实验室的初步数据 已经开始阐明Bax和心磷脂之间的相互作用机制。在存在的情况下 心磷脂 Bax 经历独特的构象变化，促进分子从 模型膜。当前项目的目标是确定这种构象的影响 Bax 的活性和功能构象发生变化。我们的目标是详细说明结构性变化 并将这些变化与 Bax 在膜上的功能联系起来。这将通过学习来实现 使用荧光光谱法观察膜相关 Bax 的孔形成和寡聚化 技术。我们还将研究 Bax 区域如何促进膜识别孔的形成和 通过使用突变体进行寡聚化。 Bax 中我们感兴趣的两个区域是 BH3 结构域， 也称为推定心磷脂结合区和 C 端疏水结构域。理解 孔形成和低聚的机制以及 Bax 结构域如何促进 膜活性构象将增强我们对细胞凋亡的理解并帮助我们能力 克服癌细胞为逃避细胞凋亡而建立的障碍。