Structural basis for substrate specificity of single domain APOBEC3s

单域 APOBEC3 底物特异性的结构基础

• 批准号: 9141792
• 负责人: Tania Vanessa Silvas
• 金额: $ 3.03万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9141792
• 关键词: AIDS/HIV problem; Active Sites; Adverse effects; Affect; Affinity; Anisotropy; Anti-HIV Agents; Anti-Retroviral Agents; Binding; Biochemical; Biological Assay; Cause of Death; Cells; Chemicals; Chimera organism; Communicable Diseases; Complex; Crystallization; Cytidine; Cytidine Deaminase; Cytosine; DNA; DNA Binding; Deamination; Dependence; Dinucleoside Phosphates; Engineering; Enzymes; Family; Foundations; G-Quartets; HIV; HIV Genome; HIV drug resistance; Homology Modeling; Human; Immune system; Immunity; Left; Mutation; Nucleic Acids; Nucleotides; Probability; Proteins; Publishing; Reverse Transcription; Series; Specificity; Structure; Substrate Specificity; Techniques; Testing; Therapeutic; Uridine; Variant; Viral; Viral Genome; Viral Physiology; Zinc; arm; base; drug development; experience; innovation; member; preference; public health relevance; skills; success; therapeutic target

 DESCRIPTION (provided by applicant): Structural basis for substrate specificity of single domain APOBEC3s Members of the APOBEC3 (A3) family of cytidine deaminases provide a first line of defense against HIV; however, HIV evades A3 restriction factors through viral infectivity factor (Vif), which antagonizes A3. The overall objective of this proposal is to elucidte the structural basis for substrate specificity of single domain APOBEC3s toward understanding HIV restrictions. A3s can inhibit HIV replication by introducing lethal mutations in the viral genome during reverse transcription. Differences in substrate specificities for deaminating ssDNA among A3 enzymes vary, yet the structural basis for substrate sequence specificity is not well understood. I hypothesize that topological and chemical differences in the active site of A3 enzymes are responsible for their substrate sequence specificities. I propose the following three aims to test my hypothesis: elucidate [1] the substrate sequence dependence of A3 affinity to ssDNA, [2] the mechanism of A3 interaction with substrate ssDNA, and [3] the correlation between homology and specificity of the active site of active A3 Z domains. Results of this proposal will not only contribute to a more comprehensive understanding of the structural basis for A3 function, but will also provide an essential foundation for new innovative anti-HIV drug development strategies.

 描述(由申请人提供)：单域APOBEC3底物特异性的结构基础APOBEC3(A3)家族胞苷脱氨酶家族成员提供了对抗HIV的第一道防线；然而，HIV通过病毒感染性因子(Vif)避开A3限制因子，从而拮抗A3。这项建议的总体目标是阐明单域APOBEC3底物特异性的结构基础，以了解HIV的限制。A3S可以通过在逆转录过程中在病毒基因组中引入致命突变来抑制艾滋病毒的复制。A3酶对脱氨基单链DNA的底物专一性不同，但底物序列专一性的结构基础还不是很清楚。我假设A3酶活性部位的拓扑和化学差异是它们底物序列特异性的原因。我提出以下三个目的来验证我的假设：阐明[1]A3与单链DNA亲和力的底物序列依赖性，[2]A3与底物单链DNA相互作用的机制，以及[3]活性A3 Z结构域活性部位的同源性和特异性之间的相关性。这一建议的结果不仅有助于更全面地了解A3功能的结构基础，还将为新的创新抗艾滋病毒药物开发战略提供必要的基础。