Viral And host mechanisms that tilt the HSV lytic/latent balance

描述（由申请人提供）：单纯疱疹病毒引起相当大的发病率和死亡率。它们在粘膜部位经历溶解性、生产性感染，并扩散到感觉神经节，在那里它们在宿主的一生中经历潜伏感染。重新激活线索 反复感染和疾病。抗病毒药物已被定义为抑制裂解感染周期，但没有针对潜伏病毒的方法。我们已经定义了 LAT 和 ICPO 等病毒基因产物在溶解和潜伏感染期间调节染色质结构中的作用，但需要有关这些机制的进一步基本信息，以发现针对 HSV 潜伏感染的治疗方法。在此应用中，我们的具体目标是：为了测试 HSV 潜伏相关转录物在三叉神经节急性感染期间和潜伏感染期间减少裂解基因表达的可能机制的假设：LAT 作为长非编码 RNA，将组蛋白修饰复合物招募到病毒基因组中，b。 LAT 作为 miRNA 的前体，通过对 miRNA 突变病毒的研究（与 Coen 实验室合作）降低 ICPO 表达，从而导致染色质变化，c。 LAT 调节 DNA 序列以顺式作用方式促进病毒裂解基因上的染色质，d．通过莱布实验室对培养神经元基因组靶向的研究，LAT 导致病毒基因组的差异靶向。 2. 明确HSV ICPO蛋白在三叉神经节急性感染和潜伏感染过程中调节染色质结构的机制。我们有令人兴奋的未发表结果，即 ICPO 突变病毒在潜伏感染期间其基因组上有不同的染色质谱。我们将验证 ICPO 通过向病毒和细胞基因招募组蛋白修饰酶来改变染色质状态的假设。 3. 定义LAT和ICPO在调节HSV染色质方面的相互作用。我们将测试以下假设：LAT 与 ICPO 转录物形成双链体 RNA，通过突变 ICPO 启动子或突变 ICPO 翻译起始位点来招募组蛋白修饰酶，并通过构建 LAT 和 ICPO 双突变病毒来确定它们对潜伏感染和病毒染色质的组合效应。 相关性：单纯疱疹病毒会引起严重的生殖器、眼部和神经系统疾病，而生殖器疱疹会增加感染艾滋病毒的风险。有一些药物可以针对单纯疱疹病毒的活跃生长，但没有一种药物可以针对潜伏感染。这项研究将明确单纯疱疹病毒潜伏感染的基本机制以及治疗这些病毒潜伏感染的潜在药物的新靶点。 项目 1：染色质和裂解/潜在平衡 项目负责人 (PL)：Knipe, David M. 描述（由申请人提供）：单纯疱疹病毒引起相当大的发病率和死亡率。它们在粘膜部位经历溶解性、生产性感染，并扩散到感觉神经节，在那里它们在宿主的一生中经历潜伏感染。重新激活线索 反复感染和疾病。抗病毒药物已被定义为抑制裂解感染周期，但没有针对潜伏病毒的方法。我们已经定义了 LAT 和 ICP0 等病毒基因产物在溶解和潜伏感染期间调节染色质结构中的作用，但需要有关这些机制的进一步基本信息，以发现针对 HSV 潜伏感染的治疗方法。在此应用中，我们的具体目标是：为了测试 HSV 潜伏相关转录物在三叉神经节急性感染期间和潜伏感染期间减少裂解基因表达的可能机制的假设：LAT 作为长非编码 RNA，将组蛋白修饰复合物招募到病毒基因组中。 b. LAT 作为 miRNA 的前体，通过对 miRNA 突变病毒的研究（与 Coen 实验室合作）降低 ICP0 表达，从而导致染色质变化。 c. LAT 调控 DNA 序列以顺式作用方式促进病毒裂解基因上的染色质。 d.通过莱布实验室对培养神经元基因组靶向的研究，LAT 导致病毒基因组的差异靶向。 2. 明确HSV ICP0蛋白在三叉神经节急性感染和潜伏感染过程中调节染色质结构的机制。我们有令人兴奋的未发表结果，即 ICP0 突变病毒在潜伏感染期间其基因组上有不同的染色质特征。我们将测试以下假设：ICP0 通过向病毒和细胞基因招募组蛋白修饰酶来改变染色质状态。 3. 定义LAT和ICP0在调节HSV染色质中的相互作用。我们将测试以下假设：LAT 形成双链体 RNA ICP0 转录本，通过突变 ICP0 启动子或突变 ICP0 翻译起始位点来招募组蛋白修饰酶，并通过构建 LAT 和 ICP0 双突变病毒来确定它们对潜伏感染和病毒染色质的组合效应。 相关性：单纯疱疹病毒会引起严重的生殖器、眼部和神经系统疾病，而生殖器疱疹会增加感染艾滋病毒的风险。 有一些药物可以针对单纯疱疹病毒的活跃生长，但没有一种药物可以针对潜伏感染。 这项研究将明确单纯疱疹病毒潜伏感染的基本机制以及治疗这些病毒潜伏感染的潜在药物的新靶点。

DESCRIPTION (provided by applicant): Herpes simplex viruses cause considerable morbidity and mortality. They undergo a lytic, productive infection at the mucosal sites and spread into sensory ganglia, where they undergo a latent infection for the life of the host. Reactivation leads to recurrent infection and disease. Antiviral drugs have been defined that inhibit the lytic infection cycle, but there are no approaches that target the latent virus. We have defined the role of viral gene products such as LAT and ICPO in modulating the chromatin structure during lytic and latent infection, but further basic information is needed about these mechanisms for discovery of therapeutics that target HSV latent infection. In this application our specific aims are: a. To test hypotheses for possible mechanisms by which the HSV latency-associated transcript reduces lytic gene expression during acute infection and during latent infection of trigeminal ganglia: LAT acts as a long noncoding RNA that recruits histone-modifying complexes to the viral genome, b. LAT leads to chromatin changes by serving as a precursor to an miRNA that reduces ICPO expression through studies of miRNA mutant viruses (with Coen lab), c. LAT regulatory DNA sequences act in a cis-acting manner to promote chromatin on the viral lytic genes, d. LAT leads to differential targeting of the viral genome through studies of genome targeting in cultured neurons with the Leib lab. 2. To define the mechanisms by which the HSV ICPO protein regulates chromatin structure during acute infection and latent infection of trigeminal ganglia. We have exciting unpublished results that ICPO mutant viruses have a different chromatin profile on their genome during latent infection. We will test the hypothesis that ICPO acts to alter the chromatin state by recruiting histone modification enzymes to viral and cellular genes. 3. To define Interactions between LAT and ICPO in regulating HSV chromatin. We will test the hypothesis that LAT forms duplex RNA with ICPO transcripts to recruit histone modifying enzymes by mutating the ICPO promoter or mutating the ICPO translational initiation site and by constructing LAT and ICPO double mutant viruses to determine their combinatorial effects on latent infection, and viral chromatin. RELEVANCE: Herpes simplex viruses cause considerable genital, ocular and nervous system disease, and genital herpes increases the risk of HIV infection. There are drugs that target the active growth of herpes simplex virus but none that target the latent infection. This research wil define basic mechanisms of herpes simplex virus latent infection and new targets for potential drugs to treat the latent infection of these viruses. Project 1: Chromatin and the lytic/latent balance Project Leader (PL): Knipe, David M. DESCRIPTION (provided by applicant): Herpes simplex viruses cause considerable morbidity and mortality. They undergo a lytic, productive infection at the mucosal sites and spread into sensory ganglia, where they undergo a latent infection for the life of the host. Reactivation leads to recurrent infection and disease. Antiviral drugs have been defined that inhibit the lytic infection cycle, but there are no approaches that target the latent virus. We have defined the role of viral gene products such as LAT and ICP0 in modulating the chromatin structure during lytic and latent infection, but further basic information is needed about these mechanisms for discovery of therapeutics that target HSV latent infection. In this application our specific aims are: a. To test hypotheses for possible mechanisms by which the HSV latency-associated transcript reduces lytic gene expression during acute infection and during latent infection of trigeminal ganglia: LAT acts as a long noncoding RNA that recruits histone-modifying complexes to the viral genome. b. LAT leads to chromatin changes by serving as a precursor to an miRNA that reduces ICP0 expression through studies of miRNA mutant viruses (with Coen lab). c. LAT regulatory DNA sequences act in a cis-acting manner to promote chromatin on the viral lytic genes. d. LAT leads to differential targeting of the viral genome through studies of genome targeting in cultured neurons with the Leib lab. 2. To define the mechanisms by which the HSV ICP0 protein regulates chromatin structure during acute infection and latent infection of trigeminal ganglia. We have exciting unpublished results that ICP0 mutant viruses have a different chromatin profile on their genome during latent infection. We will test the hypothesis that ICP0 acts to alter the chromatin state by recruiting histone modification enzymes to viral and cellular genes. 3. To define Interactions between LAT and ICP0 in regulating HSV chromatin. We will test the hypothesis that LAT forms duplex RNA ICP0 transcripts to recruit histone modifying enzymes by mutating the ICP0 promoter or mutating the ICP0 translational initiation site and by constructing LAT and ICP0 double mutant viruses to determine their combinatorial effects on latent infection, and viral chromatin. RELEVANCE: Herpes simplex viruses cause considerable genital, ocular, and nervous system disease, and genital herpes increases the risk of HIV infection. There are drugs that target the active growth of herpes simplex virus but none that target the latent infection. This research wil define basic mechanisms of herpes simplex virus latent infection and new targets for potential drugs to treat the latent infection of these viruses.