Zika Virus Capsid Protein Mediated Blockage of host microRNA machinery

寨卡病毒衣壳蛋白介导的宿主 microRNA 机制的阻断

• 批准号: 10093159
• 负责人: Zhen Zhao
• 金额: $ 43.4万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-05-01 至 2024-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10093159
• 关键词: African; Animals; Antiviral Agents; Binding; Bioinformatics; Biological Assay; Brain; Brazil; Capsid; Capsid Proteins; Cell physiology; Cells; Code; Communicable Diseases; Congenital Abnormality; Country; Development; Dicer Enzyme; Disease; Disease Outbreaks; Embryo; Endoribonucleases; Eukaryotic Cell; Family; Fetal Growth Retardation; Flaviviridae; Flavivirus; Gene Expression Regulation; Genes; Human; Immune Evasion; Impairment; In Vitro; Infection; Innate Immune System; International; Invertebrates; Investigation; Life Cycle Stages; Link; Maps; Mediating; Messenger RNA; MicroRNAs; Microcephaly; Modeling; Molecular; Molecular Target; Mus; Natural Immunity; Nervous system structure; Neurologic; Nucleotides; Outcome; Pathogenesis; Pathway interactions; Placenta; Play; Pregnancy; Process; Production; Proteins; RNA; RNA Interference; RNA Viruses; RNA-Induced Silencing Complex; Regulation; Reporting; Resistance; Ribonuclease III; Ribonucleases; Role; Small Interfering RNA; Small RNA; Surveillance Program; System; Testing; Therapeutic; Variant; Viral; Viral Genome; Viral Pathogenesis; Viral Proteins; Virulence; Virus; Virus Replication; ZIKA; ZIKV infection; Zika Virus; base; congenital zika syndrome; drug development; fetal; fighting; human disease; in utero; in vivo; induced pluripotent stem cell; insight; member; mouse model; nerve stem cell; nervous system disorder; neurodevelopment; neurogenesis; novel strategies; plant fungi; pregnant; prenatal; programs; protein protein interaction; response; stem cells; therapeutic development; transcriptome sequencing; virus host interaction

SUMMARY Zika virus (ZIKV) is a single-stranded RNA virus of the Flaviviridae family. It rapidly spread worldwide during 2015-2016 and is causally associated with fetal microcephaly, intrauterine growth retardation, and other congenital malformations. ZIKV is reported to infect placenta and fetal brain during pregnancy, particularly targeting human neural stem and progenitor cells (NSCs). Among the flavivirus family, only ZIKV is linked to microcephaly, suggesting uniqueness of ZIKV infection compared to other members, which calls for a better understanding of the molecular drivers of ZIKV immune evasion and pathogenesis in fetal brain. In addition, host molecular targets of ZIKV proteins remain elusive, which not only limits our understanding of ZIKV infection and pathogenesis, but also impedes anti-ZIKV drug development. Since the ZIKV outbreak in 2015, we have focused on understanding the complexity of ZIKV infection and pathogenesis of microcephaly. To fully understand the roles of viral proteins during ZIKV life cycle, we established the ZIKV-host interactome in human iPSC-derived NSCs. By analyzing this ZIKV-host interactome, we found that the key microRNA processing protein DICER was the top target of ZIKV capsid protein, and DICER deficiency facilitated ZIKV infection in mouse embryonic NSCs. Dysregulation of microRNAs has been associated with many human disease diseases, including developmental neurological disorders such as microcephaly. More importantly, DICER-dependent microRNA production is commonly used by plants, fungi and invertebrates, and remains active in mammalian stem cells to produce antiviral small RNAs from the viral genomes, which inhibits viral replication via RISC-mediated RNA interference. Mechanistically, we further identified that ZIKV capsid directly interacts with DICER and blocks its ribonuclease activity, dampening the production of both viral interfering RNAs and host microRNAs that are essential for neurogenesis. Therefore, we hypothesize that ZIKV can efficiently suppress the DICER-mediated antiviral viRNA pathway in host cells with its capsid protein; and by antagonizing host microRNA machinery, ZIKV capsid also intervenes neural development and causes microcephaly and other birth defects. Under the current application, we propose to further investigate capsid-dependent suppression of DICER function as a unique determinant of ZIKV immune evasion and pathogenesis, using different ZIKV strains and capsid variants in both human fetal NSCs and a mouse model of prenatal infection. By understanding the unique role of DICER in ZIKV infection and its associated microcephaly, we hope to define a capsid-dependent difference between the Brazilian and African strains (AIMs 1-2), and provide a proof-of-concept whether boosting this viRNA-dependent innate immune system is applicable as a novel approach to reverse the pathogenesis of ZIKV in fetal brain (AIMs 2-3). The outcomes of this application will also provide broader insight for other CNS infectious diseases.

摘要 寨卡病毒(ZIKV)是黄病毒科的一种单链RNA病毒。它在全球范围内迅速传播 2015-2016年，与胎儿小头畸形、胎儿宫内发育迟缓和其他 先天畸形。据报道，ZIKV在怀孕期间会感染胎盘和胎儿的大脑，尤其是 靶向人类神经干细胞和祖细胞(NSCs)。在黄病毒家族中，只有ZIKV与 小头畸形，表明与其他成员相比，ZIKV感染的独特性，这需要更好的 了解ZIKV免疫逃避的分子驱动因素及其在胎脑中的发病机制。此外，主机 ZIKV蛋白的分子靶点仍然难以捉摸，这不仅限制了我们对ZIKV感染和 发病机制，也阻碍了抗ZIKV药物的开发。 自2015年寨卡病毒爆发以来，我们一直专注于了解寨卡病毒感染的复杂性和 小头畸形的发病机制。为了充分了解病毒蛋白在ZIKV生命周期中的作用，我们 在人IPSC来源的神经干细胞中建立了ZIKV-宿主相互作用组。通过分析ZIKV-宿主互动组， 我们发现，ZIKV衣壳蛋白的首要靶标是关键的microRNA加工蛋白，而 缺陷促进了ZIKV在小鼠胚胎神经干细胞中的感染。MicroRNAs的调节失调一直是 与许多人类疾病有关，包括发育性神经疾病，如 小头畸形。更重要的是，依赖迪格尔的microRNA生产通常被植物、真菌和 无脊椎动物，并在哺乳动物干细胞中保持活跃，从病毒中产生抗病毒的小RNA 基因组，通过RISC介导的RNA干扰抑制病毒复制。从机制上讲，我们进一步 证实ZIKV衣壳直接与迪格尔相互作用并阻断其核糖核酸酶活性，抑制 产生病毒干扰RNA和宿主microRNA，这是神经发生所必需的。 因此，我们推测ZIKV可以有效地抑制Dever介导的抗病毒途径。 通过对抗宿主的microRNA机制，ZIKV衣壳也参与了 神经发育并导致小头畸形和其他先天缺陷。在目前的申请下，我们建议 进一步研究作为ZIKV免疫唯一决定因素的衣壳依赖的DICER功能抑制 使用不同的ZIKV毒株和衣壳变异体在人胚胎NSCs和a中的逃避和发病机制 小鼠产前感染模型的建立。通过了解Disher在寨卡病毒感染中的独特作用及其 相关的小头畸形，我们希望定义巴西人和非洲人之间依赖衣壳的差异 菌株(目标1-2)，并提供了是否增强这种依赖Virna的先天免疫的概念验证 该系统可作为逆转ZIKV胎脑致病机制的新途径(AIMS 2-3)。这个 这一应用的结果也将为其他中枢神经系统传染病提供更广泛的洞察力。