Martin Carolina, Leyton Luis, Hott Melissa, Arancibia Yennyfer, Spichiger Carlos, McNiven Mark A, Court Felipe A, Concha Margarita I, Burgos Patricia V, Otth Carola
Faculty of Medicine, Institute of Clinical Microbiology, Universidad Austral de ChileValdivia, Chile.
Department of Biochemistry and Molecular Biology and the Center for Basic Research in Digestive Diseases, Mayo ClinicRochester, MN, United States.
Front Cell Infect Microbiol. 2017 Aug 22;7:371. doi: 10.3389/fcimb.2017.00371. eCollection 2017.
Herpes simplex virus type 1 (HSV-1) is a ubiquitous pathogen that establishes a latent persistent neuronal infection in humans. The pathogenic effects of repeated viral reactivation in infected neurons are still unknown. Several studies have reported that during HSV-1 epithelial infection, the virus could modulate diverse cell signaling pathways remodeling the Golgi apparatus (GA) membranes, but the molecular mechanisms implicated, and the functional consequences to neurons is currently unknown. Here we report that infection of primary neuronal cultures with HSV-1 triggers Src tyrosine kinase activation and subsequent phosphorylation of Dynamin 2 GTPase, two players with a role in GA integrity maintenance. Immunofluorescence analyses showed that HSV-1 productive neuronal infection caused a scattered and fragmented distribution of the GA through the cytoplasm, contrasting with the uniform perinuclear distribution pattern observed in control cells. In addition, transmission electron microscopy revealed swollen cisternae and disorganized stacks in HSV-1 infected neurons compared to control cells. Interestingly, PP2, a selective inhibitor for Src-family kinases markedly reduced these morphological alterations of the GA induced by HSV-1 infection strongly supporting the possible involvement of Src tyrosine kinase. Finally, we showed that HSV-1 tegument protein VP11/12 is necessary but not sufficient to induce Dyn2 phosphorylation. Altogether, these results show that HSV-1 neuronal infection triggers activation of Src tyrosine kinase, phosphorylation of Dynamin 2 GTPase, and perturbation of GA integrity. These findings suggest a possible neuropathogenic mechanism triggered by HSV-1 infection, which could involve dysfunction of the secretory system in neurons and central nervous system.
单纯疱疹病毒1型(HSV-1)是一种普遍存在的病原体,可在人类神经元中建立潜伏性持续性感染。病毒在受感染神经元中反复激活的致病作用仍不清楚。多项研究报告称,在HSV-1上皮感染期间,该病毒可调节多种细胞信号通路,重塑高尔基体(GA)膜,但其中涉及的分子机制以及对神经元的功能影响目前尚不清楚。在此,我们报告用HSV-1感染原代神经元培养物会触发Src酪氨酸激酶激活以及动力蛋白2 GTP酶的后续磷酸化,这两个因素在维持GA完整性方面发挥作用。免疫荧光分析表明,HSV-1在神经元中的有效感染导致GA在细胞质中呈分散和碎片化分布,这与对照细胞中观察到的均匀核周分布模式形成对比。此外,透射电子显微镜显示,与对照细胞相比,HSV-1感染的神经元中高尔基池肿胀且堆叠紊乱。有趣的是,Src家族激酶的选择性抑制剂PP2显著减少了HSV-1感染诱导的GA的这些形态学改变,有力地支持了Src酪氨酸激酶可能参与其中。最后,我们表明HSV-1被膜蛋白VP11/12是诱导Dyn2磷酸化所必需的,但并不充分。总之,这些结果表明HSV-1神经元感染会触发Src酪氨酸激酶激活、动力蛋白2 GTP酶磷酸化以及GA完整性的扰动。这些发现提示了一种由HSV-1感染触发的可能的神经致病机制,这可能涉及神经元和中枢神经系统中分泌系统的功能障碍。