Nano-lmaging APOBECS Interactions

APOBECSG （A3G）和APOBECSF （A3F）参与多种抗病毒蛋白和核酸交易。重要的主要相互作用包括蛋白间相互作用、结合单链核酸（RNA和ssDNA）以及HIV Vif的中和作用。充分阐明这些分子间相互作用对于理解这些细胞蛋白抑制HIV复制的机制是必要的。寡聚化在其活性中的作用是一个非常重要的问题。这些都是纳米级的相互作用，AFM是解决上述问题的首选方法。AFM目前的发展水平使这种独特的仪器能够在纳米尺度上为生物分子复合物的表征提供丰富的重要信息。分子系统的地形分析是AFM应用于广泛复杂的蛋白质- dna系统的结构和特异性表征的初始领域。除了成像，原子力显微镜还能够直接测量系统内的分子相互作用，近十年来的研究导致原子力显微镜在这一领域的应用取得了巨大进展。我们的初步研究已经使我们能够提供与ssDNA底物结合的A3G的第一张图像。我们进一步预期，使用所有形式的AFM技术将帮助我们详细描述这些复合物，剖析蛋白质和化学需求，并将关键观察扩展到ASF。为达致这些总体目标，我们将致力达致以下三个具体目标：使用原子力显微镜（AFM）在纳米级分辨率下成像A3配合物（项目目标1和2）；目标2。使用力谱测量A3-ssDNA复合物内的相互作用（项目目标1和2）和目标3。利用AFM成像和探测方式表征A3-Vif相互作用（项目目标3）。本项目的研究是我们整体项目的一个组成部分，旨在全面了解A3-AS3 a3核酸和A3-Vif相互作用。

APOBECSG (A3G) and APOBECSF (A3F) are involved in various anti-viral protein and nucleic acid transactions. Important primary interactions include interprotein interactions, binding single-stranded nucleic acids (RNA and ssDNA), and neutralization by HIV Vif. The full elucidation of these intermolecular interactions is necessary to understand the mechanism by which these cellular proteins inhibit HIV replication. The role of oligomerization in their activity is an issue of great importance. These are interactions at the nanoscale level, and AFM is the method of choice capable to addressing problems listed above. AFM currently reached a level of development that enables this unique instrument to provide a wealth of important information to the characterization of biomolecular complexes at nanoscale. The topographic analysis of molecular system is the initial area of the AFM application for characterization of the structure and specificity of protein-DNA systems of a broad complexity. In addition to imaging, AFM is capable of direct measurements of molecular interaction within the system and research during this decade led to a dramatic progress in this area of the AFM applications. Our Preliminary Studies have already enabled us to provide the first images of A3G bound to ssDNA substrates. We further anticipate that the use of all modalities of AFM technology will help us detail these complexes, dissect the protein and chemical requirements, and extend key observations to ASF. To help achieve these overarching objectives, we will pursue the following three Specific Aims: Aim 1. Image A3 complexes at nanoscale resolution using AFM (Program Objectives 1 & 2); Aim 2. Measure interactions within A3-ssDNA complexes using force spectroscopy (Program Objectives 1 & 2) and Aim 3. Characterize A3-Vif interactions using AFM imaging and probing modalities (Program Objectives 3). The studies under this project are an integral component of our overall Program Project aiming to provide a comprehensive understanding of A3-AS3 A3-nucleic acid, and A3-Vif interactions. The nanoscale studies will provide a platform for evaluating any future therapeutics that function by leveraging the AS-Vif interaction.