Cryo-ET Guided Single Particle Reconstruction of HIV

摘要 人类免疫缺陷病毒1型(HIV-1)Gag晶格的原子分辨结构为 揭示了稳定HIV-1未成熟颗粒结构的关键分子接触，并告知HIV-1 1蛋白水解性裂解和Gag格子解离。为了对逆转录病毒有一个基本的了解 正病毒亚科的未成熟粒子的组装和成熟，原子分辨率图是必需的。 在这里，我们提出了一种策略，即冷冻电子断层扫描(cryo-et)制导的单粒子重建。 (SPR)，实现逆转录病毒未成熟颗粒的原子分辨率重建图。我们将使用人类 免疫缺陷病毒2型(HIV-2)作为实施这一图像处理策略的基础。我们 然后将该方法应用于其他逆转录病毒未成熟颗粒结构的研究，例如人类T细胞 白血病病毒1型(HTLV-1)，并对关键分子的保守性进行比较研究 HIV-1、HIV-2和HTLV-1 Gag晶格结构中的相互作用。我们也会将这种方法应用到研究中。 膜锚定的HIV-1包膜蛋白结构。提出了一种混合图像处理方法 利用两种低温电磁成像方法(即冷冻-ET和SPR)的优点，克服了 在处理逆转录病毒未成熟颗粒的图像时，每种方法都面临着计算挑战。

ABSTRACT The atomic resolution structures of the human immunodeficiency virus type 1 (HIV-1) Gag lattice have revealed critical molecular contacts that stabilize the HIV-1 immature particle structure and have informed HIV- 1 proteolytic cleavages and Gag lattice disassembly. In order to gain a fundamental understanding of retrovirus assembly and maturation, atomic resolution maps of immature particles for the Orthoretrovirinae are required. Here we propose a strategy, i.e., cryo-electron tomography (cryo-ET) guided single particle reconstruction (SPR), to achieve atomic resolution reconstruction maps of retrovirus immature particles. We will use human immunodeficiency virus type 2 (HIV-2) as the basis for implementation of this image processing strategy. We will then apply the method to the study of other retrovirus immature particle structures, e.g., human T-cell leukemia virus type 1 (HTLV-1), and conduct comparative studies about the conservation of key molecular interactions in HIV-1, HIV-2 and HTLV-1 Gag lattice structures. We will also apply this approach for the study of membrane anchored HIV-1 envelope protein structure. This proposed hybrid image processing method takes advantage of the strengths of both cryo-EM imaging methods (i.e. cryo-ET and SPR) and overcomes the computation challenges that each method bears when processing images of retrovirus immature particles.