Role of PISA; a PYHIN Family Member in Intracellular DNA Recognition

国际学生评估项目（PISA）的作用；

• 批准号: 8291224
• 负责人: Katherine A. Fitzgerald
• 金额: $ 40.31万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8291224
• 关键词: Adenoviruses; Area; B-DNA; Bacterial DNA; Binding; Caspase-1; Cell Line; Cells; Cleaved cell; Cytoplasm; DNA; DNA Viruses; Disease; Family; Family member; Gene Deletion; Genes; Genetic Transcription; Germ Lines; Goals; Grant; Host Defense; Human; IL18 gene; Immune response; Immune system; In Vitro; Infection; Inflammation; Inflammatory; Inflammatory Response; Interferon Type I; Interferon-beta; Interferons; Interleukin-12; Interleukin-18; Knockout Mice; Lead; Life; Ligand Binding; Ligands; Listeria monocytogenes; Mediating; Modeling; Molecular; Multiprotein Complexes; Mus; Natural Immunity; Nucleic Acids; Pattern; Pattern recognition receptor; Play; Process; Production; Proteins; RNA; RNA Helicase; Reaction; Regulation; Reporter; Rest; Role; Signal Transduction; Simplexvirus; Technology; Testing; Viral; base; chemokine; cytokine; cytosolic receptor; defined contribution; ds-DNA; gene therapy; human TLR3 protein; in vivo; marenostrin; member; microbial; mouse model; new therapeutic target; novel strategies; pathogen; prevent; procaspase-1; public health relevance; receptor; response; sensor; viral DNA

DESCRIPTION (provided by applicant): The innate immune system senses non-self nucleic acids via germ-line encoded pattern recognition receptors. RNA is sensed via Toll-like receptor (TLR)-3, -7 and -8 or by the cytoplasmic RNA helicases RIG-I and MDA-5. Little is known about sensors for cytoplasmic DNA, which when delivered to the cytoplasm trigger type I IFN gene transcription and caspase-1-mediated processing of IL-12. We have identified PISA (PYHIN protein stimulating ASC), one of four human PYHIN proteins as a receptor for cytosolic DNA. The HIN200 domain of PISA binds to DNA, while the PYD domain (but not that of PYHIN1-3) associates with the adapter molecule ASC to activate NF-:B and caspase-1. Knockdown of PISA downregulates caspase-1-mediated IL-12 responses, with concomitant increases in type I interferon production. Our hypothesis is that PISA serves to recognize microbial cytosolic DNA (such as bacterial or viral DNA) and that PISA induces pro-inflammatory responses towards cytoplasmic DNA via the assembly of an inflammasome that engages ASC and caspase-1. In this study, we propose to further characterize the role of PISA in the recognition of viral and bacterial cytosolic DNA. We will also generate a PISA knock-out mouse by gene-trap technology and/or targeted gene deletion and propose to analyze the in vivo relevance of PISA for microbial infections. Finally, we will assess the role of PISA for the modulation of interferon responses towards cytoplasmic DNA. Elucidation of the molecular mechanisms of cytosolic DNA recognition could lead to novel therapeutic targets for microbial infections and thereby enable novel strategies that could prevent inflammatory reactions to gene therapy approaches. Public Health Relevance: Pathogens are detected by receptors expressed in different areas of cells of the immune system. This grant is focused on understanding how a cytosolic protein, which we have identified called PISA (PYHIN protein stimulating ASC) senses pathogens by virtue of their DNA. Elucidation of molecular details of PISA activation could lead to novel strategies of pharmacological interference for diseases based on intracellular DNA recognition.

描述（由申请人提供）：先天免疫系统通过种系编码的模式识别受体感知非自身核酸。RNA通过Toll样受体（TLR）-3、-7和-8或通过细胞质RNA解旋酶RIG-I和MDA-5来感测。关于细胞质DNA的传感器知之甚少，当其被递送到细胞质时触发I型IFN基因转录和半胱天冬酶-1介导的IL-12加工。我们已经鉴定了比萨（PYHIN蛋白刺激ASC），其为四种人PYHIN蛋白之一，作为胞质DNA的受体。比萨的HIN 200结构域与DNA结合，而PYD结构域（但不是PYHIN 1 -3的结构域）与接头分子ASC结合以激活NF-：B和半胱天冬酶-1。敲除比萨下调半胱天冬酶-1介导的IL-12反应，伴随着I型干扰素产生的增加。我们的假设是，比萨用于识别微生物胞质DNA（如细菌或病毒DNA），并且比萨通过接合ASC和半胱天冬酶-1的炎性体的组装诱导针对胞质DNA的促炎反应。在这项研究中，我们建议进一步表征比萨在病毒和细菌胞质DNA的识别中的作用。我们还将通过基因诱捕技术和/或靶向基因缺失产生比萨敲除小鼠，并建议分析比萨与微生物感染的体内相关性。最后，我们将评估比萨的作用，对细胞质DNA的干扰素反应的调制。阐明胞质DNA识别的分子机制可能会导致微生物感染的新的治疗靶点，从而使新的策略，可以防止炎症反应的基因治疗方法。公共卫生相关性：病原体通过免疫系统细胞不同区域中表达的受体检测。这项资助的重点是了解一种胞质蛋白，我们已经确定称为比萨（PYHIN蛋白刺激ASC）如何通过它们的DNA感知病原体。阐明比萨激活的分子细节可能导致基于细胞内DNA识别的疾病的药理学干预的新策略。