MECHANISMS OF NEURONAL SKELETAL INJURY IN AIDS DEMENTIA

艾滋病痴呆的神经骨骼损伤机制

• 批准号: 2267728
• 负责人: JON S MORROW
• 金额: $ 21.79万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-05-01 至 1999-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2267728
• 关键词: AIDS dementia complex; HIV envelope protein gp120; NMDA receptors; ankyrins; antigen receptors; calcium; calmodulin; calpain; cell membrane; cytoskeletal proteins; excitatory aminoacid; gene mutation; human immunodeficiency virus; human tissue; immunoelectron microscopy; immunofluorescence technique; laboratory mouse; laboratory rabbit; neurons; neurotoxins; posttranslational modifications; protein kinase; protein transport; spectrin; tissue /cell culture

Most patients with AIDS will develop a disabling dementia characterized by memory loss, blindness, and motor disturbances. Recent evidence indicates that this is not due to infection of neurons with HIV-1, but possibly to a neurotoxic effect of the viral coat protein gp120 shed from infected cells. The mechanism of gp120 action appears in some respects to be similar to normal mechanisms of glutamate activation, and excessive stimulation of neurons with excitatory amino acids (EAA) is also neurotoxic. The molecular mechanisms by which gp120 or EAA stimulation result in lethal cellular injury are unknown, although one pathway appears to involve post-transnational alterations in the neuronal spectrin cytoskeleton. The overall goal of the proposed studies will be to understand how the neuronal spectrin cytoskeleton organizes pre- and postsynaptic receptors, stabilizes the neuronal membrane, and is altered by gp120 and EAA action. Specifically, research will focus on the factors which sort unique isoforms of spectrin, ankyrin, and adducing to the pre-or postsynaptic membrane, and regulate the interactions between these proteins and with other components of the neuronal membrane. Neurons specific components of interest include a putative non CD4 gp120 receptor and the NMDA receptor. Regulatory events acting on the spectrin skeleton to be examined include u-calpain mediated proteolysis, Ca++ and calmodulin, and phosphorylation by cAMP dependent and independent kinases, calmodulin kinases, and protein kinase C. The distribution of unique isoforms and of post-translationally modified proteins are identified in normal and AIDS patient's brain by immunofluorescent and immuno-EM using monoclonal and sequence specific antibodies; interactions between purified or recombinant protein components are characterized by in vitro assay, their rate of incorporation into the neuronal cytoskeleton and post-transnational modification after EAA or recombinant gp120 stimulation are studied in cultured neuronal cells. Functional sites in spectrin critical for in vivo assembly at the neuronal membrane or for (functional) linkage to the gp120 or NMDA receptors will be identified by the ability of expressed recombinant wild type and mutated proteins to associate with the membrane in cultured neuronal cells, and be post-translationally modified following receptor activation.

大多数艾滋病患者都会发展出残疾的痴呆症的特征 通过记忆力丧失，失明和运动障碍。 最近的证据 表明这不是由于HIV-1神经元的感染，而是 可能对病毒外套蛋白GP120的神经毒性作用从 感染细胞。 GP120动作的机制在某些方面出现 类似于谷氨酸激活的正常机制，过多 用兴奋性氨基酸（EAA）刺激神经元也是 神经毒性。 GP120或EAA刺激的分子机制 导致致命的细胞损伤是未知的，尽管一条途径 似乎涉及神经元的转变后变化 光谱细胞骨架。 拟议研究的总体目标是 了解神经元细胞骨架如何组织前和 突触后受体，稳定神经元膜，并改变 由GP120和EAA动作。 具体而言，研究将重点放在 分类光谱，arnkyrin的独特同工型的因素，并为 前或突触后膜，并调节 这些蛋白质以及神经元膜的其他成分。 神经元的特定感兴趣的组成部分包括推定的非CD4 GP120 受体和NMDA受体。 作用于光谱的监管事件 要检查的骨骼包括U-钙蛋白酶介导的蛋白水解，Ca ++和 钙调蛋白和营地依赖和独立的磷酸化 激酶，钙调蛋白激酶和蛋白激酶C. 独特的同工型和翻译后修饰的蛋白质是 通过免疫荧光和 使用单克隆和序列特异性抗体免疫EM；互动 纯化或重组蛋白成分之间的特征是 体外测定，将其掺入神经元的速率 EAA或重组后的细胞骨架和翻译后修饰 在培养的神经元细胞中研究了GP120刺激。 功能 光谱中的位点对于神经元膜的体内组件至关重要 或（功能性的）连接到GP120或NMDA受体将是 通过表达重组野生型和突变的能力确定 蛋白质与培养的神经元细胞中的膜相关，并 在受体激活后，在翻译后修饰。