Implication of RNase H domain on dimer stability and drug sensitivity of HIV-1 RT

RNase H 结构域对 HIV-1 RT 二聚体稳定性和药物敏感性的影响

• 批准号: 8541412
• 负责人: Virendra Nath PANDEY
• 金额: $ 18.68万
• 依托单位: RBHS-NEW JERSEY MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8541412
• 关键词: Active Sites; Affect; Affinity; Amino Acids; Anti-HIV Agents; Appearance; Binding; C-terminal; Calorimetry; Cleaved cell; Co-Immunoprecipitations; DBL Oncoprotein; Development; Dimerization; Disease; Distal; Drug resistance; Effectiveness; Enzyme Stability; Enzymes; HIV-1; Hydrophobic Interactions; Location; Molecular Conformation; Mutation; N-terminal; Pharmaceutical Preparations; Polymerase; Positioning Attribute; Property; RNA-Directed DNA Polymerase; Regimen; Reporting; Ribonuclease H; Role; Site; Structure; Titrations; base; clinically relevant; dimer; drug development; drug sensitivity; mutant; non-nucleoside reverse transcriptase inhibitors; pressure; public health relevance; resistance mechanism; resistant strain; therapeutic target; three dimensional structure

DESCRIPTION (provided by applicant): The connection subdomain and RNase H domain of HIV-1 RT have recently been implicated in the emergence of HIV-1 strains that are resistant to NRTI and NNRTI drugs. Site-specific mutations in the connection subdomain and RNase H domain reportedly affect substrate or NRTI binding affinity and other polymerase-related properties such as processivity, suggesting that definitive long-distance cross-talk occurs between the polymerase domain and these two distantly located structural units of HIV-1 RT. Numerous mechanisms, including a reduction in RNase H cleavage activity, which decreased template switching, and improper positioning of template-primer substrate have been proposed to explain the drug-resistant mutations. Based on the three-dimensional (3D) structure of HIV-1 RT, we propose that hydrophobic residues at the C-terminal region of the RNase H domain interacting with the C-terminal connection subdomain may be structurally important in subunit dimerization; any mutational changes in these regions may affect dimer stability and the substrate binding affinity of HIV-1 RT. We propose to investigate the implications of mutations of hydrophobic residues at the interface of the connection subdomain and RNase H domain of HIV-1 RT with respect to dimer stability and drug sensitivity of the enzyme. We will also include clinically relevant drug-resistant mutations that emerge in connection and RNase H under drug pressure.

描述（由申请人提供）：HIV-1 RT的连接子域和RNase H结构域最近与对NRTI和NNRTI药物具有抗性的HIV-1菌株的出现有关。据报道，连接子域和RNase H结构域中的位点特异性突变会影响底物或NRTI结合亲和力以及其他聚合酶相关的特性，例如加工性，这表明确定的长距离交叉态发生了聚合酶结构域与HIV-1 RT的这两个较远位于这两个位置的结构单位之间。已经提出了许多机制，包括减少模板切换的RNase H裂解活性的降低以及模板培养子底物的不当定位以解释抗药性突变。基于HIV-1 RT的三维（3D）结构，我们提出，RNase H结构域的C末端区域的疏水残基与C末端连接子域相互作用在亚基二聚体中可能在结构上很重要。这些区域的任何突变变化都可能影响HIV-1 RT的二聚体稳定性和底物结合亲和力。我们建议研究HIV-1 RT的连接子域和RNase H结构域的疏水残基突变与酶的二聚体稳定性和药物敏感性有关的界面。我们还将包括在药物压力下与RNase H相关的临床耐药突变。