Regulation of beta-catenin in neurons during the HSV-1 latency-reactivation cycle.

项目主任/首席调查员(最后、第一、中间)：琼斯，克林顿，J 项目总结(见说明)： 单纯疱疹病毒1型感染小鼠后脑干和三叉神经节神经元 (Tg)是延迟的主要位置。潜伏期的重新激活在这些相同的解剖结构中持续发生 外植体后的部位组织或热休克所致应激。与生产性感染相比，潜伏期 相关转录本(LAT)是唯一在潜伏感染神经元中大量表达的病毒基因。近期 研究表明，β-连环蛋白和β-连环蛋白共激活，高迁移率族AT-Hook1蛋白 (HMGA1)在潜伏感染HSV-1的小鼠的TG神经元中检测到，而在HSV-1感染的小鼠的TG神经元中未检测到 未受感染的小鼠。相比之下，Wnt拮抗剂dickopf 1(DKK-1)蛋白已被报道为 导致神经变性，是在外植体诱导的潜伏期重新激活过程中诱导的。的表达 后来在小鼠神经母细胞瘤细胞中稳定了β-连环蛋白的表达，这与增强 细胞存活。由于典型的Wnt/β-Catenin信号通路促进神经发生和神经元 生存，我们假设Wnt/β-catenin信号通路与LAT协同调节HSV- 1延迟-重新激活周期。针对特定目标1的研究将比较β-连环蛋白、HMGA1和DKK-1 LAT感染后潜伏期-再激活周期脑干和三叉神经节神经元的表达 无突变病毒或野生型HSV-1。调节Wnt/β-连环蛋白信号通路的小分子将 也要检查它们对延迟重新激活的影响。特定目标2的研究将确定LAT 调节β-连环蛋白表达的重要功能及其与β-连环蛋白相互作用的研究 干扰神经母细胞瘤细胞和小鼠的细胞凋亡。这些研究将为我们提供对 Wnt/β-catenin信号通路调节HSV1潜伏期-再激活周期的机制。 HSV-1潜伏期-再激活周期导致脑炎、包括间质在内的复发性眼病 角膜炎，以及人类的生殖器损伤。目前，还没有HSV-1疫苗或治疗策略 这特别干扰了潜伏期的重新激活。虽然LAT是一个重要的调节器 潜伏期-再激活周期，调节Wnt/β-连环蛋白信号通路的细胞因子可能介导 在延迟-重新激活周期中的关键步骤。 相关性(请参阅说明)： 发生反复的单纯疱疹病毒1型(HSV-1)感染是因为病毒可以建立、维持和 从延迟中重新激活。Lat是唯一在潜伏感染神经元中大量表达的病毒基因。 这项建议中的研究将检验Wnt/β-连环蛋白信号通路与LAT合作的作用 以调节潜伏期-重新激活周期。

Program Director/Principal Investigator (Last, First, Middle): Jones, Clinton, J PROJECT SUMMARY (See instructions): Following infection of mice with herpes simplex virus 1 (HSV-1), neurons in brainstem and trigeminal ganglia (TG) are primary sites for latency. Reactivation from latency consistently occurs in these same anatomical sites following explant of tissue or heat shock induced stress. In contrast to productive infection, the latency associated transcript (LAT) is the only viral gene abundantly expressed in latently infected neurons. Recent studies demonstrated that β-catenin and the β-catenin coactivator, High-Mobility Group AT–Hook 1 protein (HMGA1) were detected in TG neurons of mice latently infected with HSV-1 but not TG neurons of uninfected mice. In contrast, the Wnt antagonist, dickopf 1 (DKK-1) protein, which has been reported to cause neuro-degeneration, was induced during explant-induced reactivation from latency. Expression of LAT in mouse neuroblastoma cells stabilized β-catenin protein expression, which correlated with enhanced cell survival. Since the canonical Wnt/β-catenin signaling pathway promotes neurogenesis and neuronal survival, we hypothesize that the Wnt/β-catenin signaling pathway cooperates with LAT to regulate the HSV- 1 latency-reactivation cycle. Studies in Specific Aim 1 will compare β-catenin, HMGA1, and DKK-1 expression in brainstem and TG neurons during the latency-reactivation cycle following infection with a LAT null mutant virus or wild-type HSV-1. Small molecules that regulate the Wnt/β-catenin signaling pathway will also be examined for their effects on reactivation from latency. Studies in Specific Aim 2 will identify LAT functions important for mediating β-catenin expression and examine how LAT and β-catenin cooperate to interfere with apoptosis in neuroblastoma cells and mice. These studies will provide insight into the mechanism by which the Wnt/β-catenin signaling pathway regulates the HSV-1 latency-reactivation cycle. The HSV-1 latency-reactivation cycle is responsible for encephalitis, recurrent eye disease, including stromal keratitis, and genital lesions in humans. At this point, there are no HSV-1 vaccines or therapeutic strategies that specifically interfere with the reactivation from latency. Although LAT is an important regulator of the latency-reactivation cycle, cellular factors that regulate the Wnt/β-catenin signaling pathway may mediate crucial steps during the latency-reactivation cycle. RELEVANCE (See instructions): Recurrent herpes simplex virus 1 (HSV-1) infections occur because the virus can establish, maintain, and reactivate from latency. LAT is the only viral gene abundantly expressed in latently infected neurons. Studies in this proposal will examine the role that the Wnt/β-catenin signaling pathway cooperates with LAT to regulate the latency-reactivation cycle.