Biochemical Mechanisms of Drug Resistance in HIV-1 RT

HIV-1 RT 耐药的生化机制

• 批准号: 6837718
• 负责人: WALTER A SCOTT
• 金额: $ 37.88万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-01-15 至 2008-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6837718
• 关键词: RNA directed DNA polymerase; drug resistance; enzyme activity; enzyme mechanism; enzyme structure; enzyme substrate; foscarnet; gel mobility shift assay; human immunodeficiency virus 1; human subject; lymphocyte; macrophage; monocyte; nucleic acid chemical synthesis; nucleotides; patient oriented research; reverse transcriptase inhibitors; tissue /cell culture

DESCRIPTION (provided by applicant): Nucleoside reverse transcriptase (RT) inhibitors play an important role in therapy for HIV-1 infection and AIDS; however, long-term use of these drugs is limited by the selection of resistant mutants. These compounds give rise to chain-terminating nucleotides that are incorporated by HIV-1 RT and block further DNA chain elongation. Work from this laboratory was instrumental in showing that HIV-1 RT can catalyze the excision in vitro of chain-terminating nucleotides by transfer to a nucleotide acceptor and that a major class of nucleoside resistant mutants of HIV-1 encodes RT with increased nucleotide-dependent excision activity. Research is proposed to (a) define factors that determine the efficiency of the excision reaction in vitro including structural features of the acceptor substrate, structure of the chain-terminating residue, and sequence elements in the primer-template, (b) investigate the mechanism of inhibition of excision and DNA synthesis by foscarnet (PFA), a structural analog of pyrophosphate, and to determine the mechanism of resistance to PFA by PFA-resistant mutants, (c) investigate the effect of non-nucleoside RT inhibitors on excision and on dNTP inhibition of excision, and (d) to identify factors that determine which intracellular compounds serve as acceptor substrates for excision in vivo -- i.e., in lymphocytes from uninfected and HIV-1 infected individuals. In addition, research is proposed to extend these studies to identify factors that control excision in vivo using an enzymatic assay to detect the products of excision. The goal of this research is to define the role of the excision activity in HIV-1 infection, which will be crucial for the development of more effective drugs and therapeutic strategies against HIV, particularly against the emergence of resistant virus.

描述（由申请人提供）：核苷逆转录酶（RT）抑制剂在HIV-1感染和AIDS治疗中起重要作用；但是，这些药物的长期使用受到抗性突变体的选择限制。这些化合物引起了链末端的核苷酸，这些核苷酸由HIV-1 RT掺入并阻断进一步的DNA链伸长。该实验室的工作有助于表明HIV-1 RT可以通过转移到核苷酸受体转移到链终止的核苷酸的体外催化切除术，并且一类主要的HIV-1 HIV-1耐核苷耐药突变体与核苷酸依赖性的核苷酸依赖性降解活性增加了RT。 Research is proposed to (a) define factors that determine the efficiency of the excision reaction in vitro including structural features of the acceptor substrate, structure of the chain-terminating residue, and sequence elements in the primer-template, (b) investigate the mechanism of inhibition of excision and DNA synthesis by foscarnet (PFA), a structural analog of pyrophosphate, and to determine the mechanism of resistance to PFA by PFA耐药突变体，（c）研究非核苷RT抑制剂对切除和DNTP抑制切除的影响，以及（d）确定确定哪些细胞内化合物的因素，可作为在体内切除的受体底物，即在体内 - 即在未感染的淋巴细胞中和HIV-1感染的个体中。此外，提出研究以扩展这些研究，以鉴定使用酶测定来检测切除产物的体内切除的因素。这项研究的目的是定义切除活性在HIV-1感染中的作用，这对于开发更有效的药物和针对HIV的治疗策略至关重要，尤其是抵抗抗性病毒的出现。