Interactions Between HIV Gag and Exosomal Proteins

HIV Gag 和外泌体蛋白之间的相互作用

• 批准号: 7016241
• 负责人: Francisco Gonzalez-Scarano
• 金额: $ 10.34万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7016241
• 关键词: AIDS dementia complex; HIV infections; animal tissue; annexins; binding sites; gag protein; gene mutation; human tissue; macrophage; microglia; protein localization; protein protein interaction; protein structure function; virus infection mechanism

HIV associated Dementia (HAD) is an important co-morbidity of HIV infection. Its less severe form appears to be resistant to highly active anti-retroviral therapy (HAART) and HIV infected macrophages (MDM) and microglia are key to its development. Because of their importance in this and other facets of HIV infection, the cycle in MDM has been studied extensively, and most investigators believe that macrophage infection can be long-lived and produce little cytopathology, making these cells ideal potential reservoirs for the virus in a treated individual, and that while most steps in the infectious process parallel those in lymphocytes, virus assembly and egress are different, and involve intracytoplasmic assembly and routing into multivesicular bodies (MVBs) in preference to budding at the plasma membrane. Subsequent release of virus is believed to take place via an exocytotic pathway involving direct fusion of plasma and MVB limiting membranes. Using a model microglia/macrophage infection that has been modified so that there is low production of virus, we have identified binding between gag and an annexin II (Anx2), a pleiotropic protein involved in exosomal formation and fusion. This protein is expressed to high levels in macrophages and microglia, particularly in the infected brain. In this proposal we will develop these preliminary results in three specific aims. In the first aim, we will further determine the effects of reduction of Anx2 in MDM on HIV infection, and analyze the differences between the protein expressed in activated vs. non-activated MDM. In the second specific aim, we will map the binding sites between p55/p24 and Anx2 and introduce mutations into HIV proviruses, to determine the effects on viral infection. In the third specific aim we will study its surface expression and study Anx2 distribution in the HIV and SIV infected brain, and perform collocation experiments using fluorescence tagged molecules. These results will expand our understanding of lentiviral infection of macrophages, and potentially provide an additional target for therapeutic intervention in HIV and HAD.

HIV相关痴呆（HAD）是HIV感染的重要合并症。其不太严重的形式似乎对高度活跃的抗逆转录病毒疗法（HAART）和HIV感染巨噬细胞（MDM）和小胶质细胞具有抗性。由于它们在HIV感染的这一和其他方面的重要性，因此对MDM的周期进行了广泛的研究，大多数研究人员认为，巨噬细胞感染可以长期存在，几乎没有细胞病理学，使这些细胞在有条理的个体中对病毒的理想潜在储层，而在莱姆脑中的感染过程中，大多数人都可以在莱姆刺的感染过程中进行阶梯，而这一步骤是 组装和出口不同，涉及胞质内组装并将其路由到多囊体（MVB）中，而不是在质膜上发芽。随后的病毒释放被认为是通过涉及血浆和MVB限制膜直接融合的胞吐途径进行的。使用已修饰的模型小胶质细胞/巨噬细胞感染，以使病毒的产生较低，我们已经确定了GAG和膜联蛋白II之间的结合（Anx2），这是一种与外泌体形成和融合有关的多效蛋白。该蛋白在巨噬细胞和小胶质细胞中表达高水平，尤其是在感染的大脑中。在此提案中，我们将以三个特定的目标发展这些初步结果。在第一个 目的，我们将进一步确定MDM中Anx2减少对HIV感染的影响，并分析激活的MDM与非激活的MDM中表达的蛋白质之间的差异。在第二个特定目的中，我们将绘制p55/p24和Anx2之间的结合位点，并将突变引入HIV病毒中，以确定对病毒感染的影响。在第三个特定目的中，我们将研究其表面表达，并研究HIV和SIV感染大脑中的Anx2分布，并使用荧光标记的分子进行搭配实验。这些结果将扩大我们对巨噬细胞慢病毒感染的理解，并有可能为艾滋病毒和患有治疗性干预提供了额外的靶标。