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: 8707365
• 负责人: Virendra Nath PANDEY
• 金额: $ 23.85万
• 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 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8707365
• 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的连接子结构域和RNase H结构域最近与对NRTI和NNRTI药物耐药的HIV-1菌株的出现有关。据报道，连接子结构域和RNase H结构域的位点特异性突变会影响底物或NRTI结合亲和力以及其他与聚合酶相关的特性，如亲和性，这表明聚合酶结构域与HIV-1 rt的这两个距离较远的结构单元之间发生了明确的长距离串导。模板引物底物定位不当被认为是导致耐药突变的原因。基于HIV-1 RT的三维（3D）结构，我们提出RNase H结构域c端区域与c端连接子结构域相互作用的疏水残基可能在亚基二聚化中具有重要的结构意义；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连接子结构域和RNase H结构域界面的疏水残基突变对该酶的二聚体稳定性和药物敏感性的影响。我们还将包括在药物压力下连接和RNase H中出现的临床相关耐药突变。