DNA structure modification by the Schlafen protein family

Schlafen 蛋白家族对 DNA 结构的修饰

• 批准号: 9238658
• 负责人: MICHAEL DAVID
• 金额: $ 18.11万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-03-07 至 2019-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9238658
• 关键词: ATP phosphohydrolase; ATPase Domain; Alternative Splicing; Antibodies; Antineoplastic Agents; Antiviral Agents; Attention; Attenuated; Autoimmune Diseases; B-DNA; Binding; Biological; Biological Process; Biology; Caenorhabditis elegans; Cancer cell line; Cell Line; Cells; Codon Nucleotides; Communicable Diseases; DNA; DNA Binding; DNA Binding Domain; DNA Damage; DNA Structure; Data; Derivation procedure; Diagnostic; Down-Regulation; Drosophila genus; ERG gene; Elements; Employee Strikes; Family; Funding; Funding Agency; Generations; Genes; Genetic; Goals; HIV; Hand; Human; IRF3 gene; Immune response; Immunologics; Infection; Infection prevention; Innate Immune Response; Interferon-alpha; Interferons; Investigation; Kinetics; Laboratories; Left; Length; Link; Lupus Erythematosus; Messenger RNA; Modernization; Modification; N-terminal; Nucleic Acid Conformation; Nucleic Acids; Organism; Pathway interactions; Pharmacology; Physiological; Play; Poxviridae; Process; Production; Protein Biosynthesis; Protein Family; Protein Isoforms; Proteins; Publishing; RNA; RNA Helicase; Research; Research Personnel; Resistance; Resistance development; Retroviridae; Role; Simian virus 40; Structure; Surface; System; Techniques; Technology; Testing; Therapeutic Intervention; Time; Transfer RNA; Vaccine Adjuvant; Viral; Viral Proteins; Virus; Virus Diseases; Work; Yeasts; Z-DNA Binding Protein; Z-Form DNA; adaptive immune response; antitumor drug; base; cancer cell; chemotherapeutic agent; cytotoxic; experimental study; genome-wide analysis; helicase; immunogenic; in vivo; insight; interest; member; neoplastic cell; novel; pathogen; prevent; prospective; public health relevance; small molecule; tool; vaccine development

 DESCRIPTION (provided by applicant): The innate immune response is not antigen-specific, and is composed of the interferon (IFN) system as well as cell-based anti-pathogen countermeasures that restrict the replication of pathogens. Understanding the innate immune response and the pathways that promote or restrict the kinetics of different steps of infection is essential for devising novel pharmacological strategies for therapeutic intervention during these infectious disease processes, to develop diagnostic tools or to prevent infection. Interferons exert their antiviral effects through the induction of Interferon Stimulated early response Genes (ISGs). An expanding family of such ISGs are the Schlafen (Slfn) genes, which in addition to IFN are also directly induced by pathogen contact with the cells. In our quest to define the biological function of Slfn proteins we discovered that huSlfn11 potently inhibits the production of retroviruses including HIV. Our studies revealed huSlfn11 expression had no effect on the early steps of the infection cycle, but that huSlfn11 protein acts at the very late stages of replication where new viral proteins are synthesized. A striking hallmark of huSlfn11 function is the selective inhibition of the synthesis of virus-encoded proteins, whereas production host cell proteins are apparently unhindered. Most recently, genome-wide screening efforts from two independent laboratories employing dozens of cancer cells lines identified an intriguing correlation between huSlfn11 expression and sensitivity of cells to DDAs. Using cell lines we generated during our previous studies which specifically lack huSlfn11, we find that indeed such cells are resistant to the cytotoxic effects of several classes of DDAs. It is therefore quite reasonable to consider that the development of resistance of tumor cells against DDAs involves the down- regulation of huSlfn11. Finally, our newest studies revealed that huSlfn 5 and 11 have the ability to bind and/or generate Z-DNA. As the structure of the Z-DNA double helix is considerably different from that of B-DNA it supports different interactivity with other molecules, and a few proteins have been identified that selectively bind to Z-DNA but not to B-DNA. It is also notable that unlike B-DNA, Z-DNA is very immunogenic which has not only allowed for the production of highly specific antibodies for research purposes, but has also given rise to anti-Z-DNA antibodies in autoimmune disease such as lupus erythematosus. Although the left-handed Z-DNA and Z-RNA forms were discovered decades ago, their biological role has remained a mystery, largely because little information exists on their formation under physiological conditions. So for several decades not much insight had surfaced on Z-DNA function. In fact, since the end of the 1980s the biology of Z-DNA was not receiving much attention from researchers or funding agencies, and with a few exceptions focused on the role of Z-DNA in genetic instabilities. Our discovery of Z-D/RNA generation by Slfns, a family of interferon-induced antiviral proteins, has the strong potential to place these left-handed nucleic acids into numerous immune response scenarios. Understanding of the biological roles of Z-D/RNA is elementary to exploit their prospective pharmacological possibilities in the development of vaccine adjuvants, anti-viral or anti-neoplastic chemotherapeutics.

 描述(申请人提供)：先天免疫反应不是抗原特异性的，由干扰素(干扰素)系统和限制病原体复制的基于细胞的抗病原体对策组成。了解先天免疫反应和促进或限制感染不同步骤的动力学的途径对于设计新的药理学策略在这些传染病过程中进行治疗干预、开发诊断工具或预防感染至关重要。干扰素通过诱导干扰素刺激的早期反应基因(ISGs)发挥抗病毒作用。这类ISG的一个不断扩大的家族是Schlafen(Slfn)基因，除了干扰素外，这种基因也是由病原体与细胞接触直接诱导的。在我们寻求确定slfn蛋白的生物学功能的过程中，我们发现huslfn11有效地抑制了包括HIV在内的逆转录病毒的产生。我们的研究表明，huslfn11的表达对感染周期的早期步骤没有影响，但huslfn11蛋白在复制的非常后期阶段发挥作用，在那里合成新的病毒蛋白。HuSLfn11功能的一个显著特点是选择性地抑制病毒编码蛋白的合成，而产生宿主细胞蛋白显然不受阻碍。最近，来自两个独立实验室的全基因组筛选工作使用了数十个癌细胞株，发现了huSLfn11表达与细胞对DDA的敏感性之间有趣的相关性。使用我们在之前的研究中建立的特别缺乏huslfn11的细胞系，我们发现确实这样的细胞对几类DDA的细胞毒作用具有抵抗力。因此，认为肿瘤细胞对DDA的耐药性的形成涉及huSLfn11的下调是相当合理的。最后，我们的最新研究表明，huslfn 5和11具有结合和/或产生Z-DNA的能力。由于Z-DNA双螺旋的结构与B-DNA的结构有很大的不同，它支持与其他分子不同的相互作用， 一些蛋白质已被鉴定为选择性地与Z-DNA结合，但不与B-DNA结合。同样值得注意的是，与B-DNA不同，Z-DNA具有很强的免疫原性，不仅可以产生用于研究目的的高度特异性抗体，而且还可以在红斑狼疮等自身免疫性疾病中产生抗Z-DNA抗体。尽管左撇子Z-DNA和Z-RNA形式在几十年前就被发现了，但它们的生物学作用仍然是一个谜，主要是因为关于它们在生理条件下形成的信息很少。因此，几十年来，人们对Z-DNA的功能并没有太多的了解。事实上，自20世纪80年代末以来，Z-DNA的生物学并没有受到研究人员或资助机构的太多关注，除了少数例外，关注的是Z-DNA在遗传不稳定性中的作用。我们发现了由干扰素诱导的抗病毒蛋白家族SLfns产生Z-D/RNA，这一发现具有将这些左旋核酸置于多种免疫反应场景中的强大潜力。了解Z-D/RNA的生物学作用是开发其在疫苗佐剂、抗病毒或抗肿瘤化疗药物开发中的潜在药理学可能性的基础。