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: 9923759
• 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/9923759
• 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.

概括 Zika病毒（ZIKV）是Flaviviridae家族的单链RNA病毒。它在全球范围内迅速传播 2015-2016，与胎儿小头畸形，宫内生长迟缓和其他 先天性畸形。据报道，ZIKV在怀孕期间感染了胎盘和胎儿大脑，特别是 靶向人类神经茎和祖细胞（NSC）。在Flavivivirus家族中，只有ZIKV与 与其他成员相比，小头畸形表明ZIKV感染的独特性，这要求更好 了解ZIKV免疫逃避和发病机理的分子驱动因素。另外，主持人 ZIKV蛋白的分子靶标仍然难以捉摸，这不仅限制了我们对ZIKV感染和 发病机理，但也阻碍了抗ZIKV药物的发展。 自2015年的ZIKV爆发以来，我们一直致力于了解ZIKV感染的复杂性和 小头畸形的发病机理。为了充分了解ZIKV生命周期中病毒蛋白的作用，我们 在人IPSC衍生的NSC中建立了ZIKV-host Interactome。通过分析这个zikv-host Interactome， 我们发现，关键的microRNA加工蛋白夹子是ZIKV衣壳蛋白的最高靶标，而DICER是 缺乏促进小鼠胚胎NSC中的ZIKV感染。 microRNA的失调一直是 与许多人类疾病疾病有关，包括发育神经系统疾病，例如 小头畸形。更重要的是，植物，真菌和 无脊椎动物，并保持活性在哺乳动物干细胞中，从病毒中产生抗病毒小RNA 基因组，通过RISC介导的RNA干扰抑制病毒复制。从机械上讲，我们进一步 确定ZIKV CAPSID直接与DICER相互作用并阻止其核糖核酸酶活性，从而抑制 生产病毒干扰RNA和宿主的微洋纳斯，这对于神经发生至关重要。 因此，我们假设ZIKV可以有效地抑制迪切尔介导的抗病毒药virna途径 带有衣壳蛋白的宿主细胞；通过对抗主机MicroRNA机械，ZIKV CAPSID也介入 神经发育并导致小头畸形和其他先天缺陷。在当前申请下，我们建议 为了进一步研究dicer函数的衣壳依赖性抑制作用作为ZIKV免疫的独特决定因素 逃避和发病机理，在人胎儿NSC和A中使用不同的ZIKV菌株和衣壳变体 小鼠产前感染的模型。通过了解DICER在ZIKV感染中的独特作用及其 相关的小头畸形，我们希望定义巴西和非洲人之间的capsid依赖性差异 菌株（目标1-2），并提供概念证明，是否可以增强这种依赖性的先天性免疫 系统适用于一种扭转胎儿大脑中ZIKV发病机理的新方法（AIMS 2-3）。这 该应用程序的结果还将为其他中枢神经系统传染病提供更广泛的见解。