Mechanisms of Antiviral Drug Resistance, Host Factors and Retroviral Replication

大多数核苷和非核苷逆转录酶 (RT) 抑制剂（分别为 NRTI 和 NNRTI）的临床耐药性研究分析 RT 的前 300 个氨基酸，不包括 C 端连接子结构域 (CN) 或 RNase H 结构域 (RH)。我们观察到 CN 和 RH 中的几个突变降低了 RNase H 活性，从而影响 RNA 降解和核苷酸切除之间的平衡，并增强 NRTI 抗性。我们最近的研究表明，CN 和 RH 的突变也可以增加对 NNRTI 的耐药性，并提出了可以增加对两类 RT 抑制剂的耐药性的平行机制。据观察，CN突变存在于未接受药物治疗的患者中，我们正在探索在开始抗病毒治疗之前选择CN突变的机制。在研究 A3G 定位与 P 体的功能相关性时，我们发现 P 体相关蛋白 Mov10 通过减少病毒产生和抑制逆转录来有效抑制 HIV-1 复制。我们正在阐明 Mov10 抑制 HIV-1 颗粒产生和逆转录的机制。在检查 A3G 和 A3F 对病毒 DNA 整合的影响时，我们观察到靶细胞中的尿嘧啶 DNA 糖基化酶活性，而不是病毒生产细胞中的尿嘧啶 DNA 糖基化酶活性，导致了负链 DNA 的切口。我们正在探索这种意想不到的表型对病毒复制的重要性。 [对应于2011年10月HIV耐药项目实地考察报告中的Pathak项目3]

Most studies of clinical drug resistance to nucleoside and nonnucleoside reverse transcriptase (RT) inhibitors (NRTIs and NNRTIs, respectively) analyze the first 300 amino acids of RT and do not include the C-terminal connection subdomain (CN) or the RNase H domain (RH). We observed that several mutations in the CN and RH reduce RNase H activity, thereby affecting the balance between RNA degradation and nucleotide excision, and enhancing NRTI resistance. Our recent studies have demonstrated that mutations in the CN and the RH can also increase resistance to NNRTIs, and suggest a parallel mechanism by which resistance to both classes of RT inhibitors can be increased. It has been observed that CN mutations are present in drug-naive patients, and we are exploring the mechanisms by which CN mutations may be selected prior to initiation of antiviral therapy. While investigating the functional relevance of A3G localization to P bodies, we found that P body-associated protein Mov10 potently inhibits HIV-1 replication by reducing virus production and inhibiting reverse transcription. We are elucidating the mechanisms by which Mov10 inhibits HIV-1 particle production and reverse transcription. While examining the effects of A3G and A3F on viral DNA integration, we observed that uracil DNA glycosylase activity in the target cells, not the virus producer cells, results in nicking of the minus-strand DNA. We are exploring the significance of this unexpected phenotype to viral replication. [Corresponds to Pathak Project 3 in the October 2011 site visit report of the HIV Drug Resistance Program]