Abstract:
Herpes simplex virus 1 (HSV-1) enters sensory neurons with the potential for productive or latent infection. For either outcome, HSV-1 must curtail the intrinsic immune response, regulate viral gene expression, and remove host proteins that could restrict viral processes. Infected cell protein 0 (ICP0), a virus-encoded E3 ubiquitin ligase, supports these processes by mediating the transfer of ubiquitin to target proteins to change their location, alter their function, or induce their degradation. To identify ubiquitination targets of ICP0 during productive infection in sensory neurons, we immunoprecipitated ubiquitinated proteins from primary adult sensory neurons infected with HSV-1 KOS (wild-type), HSV-1 n212 (expressing truncated, defective ICP0), and uninfected controls using anti-ubiquitin antibody FK2 (recognizing K29, K48, K63 and monoubiquitinated proteins), followed by LC-MS/MS and comparative analyses. We identified 40 unique proteins ubiquitinated by ICP0 and 17 ubiquitinated by both ICP0 and host mechanisms, of which High Mobility Group Protein I/Y (HMG I/Y) and TAR DNA Binding Protein 43 (TDP43) were selected for further analysis. We show that ICP0 ubiquitinates HMG I/Y and TDP43, altering protein expression at specific time points during productive HSV-1 infection, demonstrating that ICP0 manipulates the sensory neuronal environment in a time-dependent manner to regulate infection outcome in neurons.
摘要:
单纯疱疹病毒1(HSV-1)进入感觉神经元,具有生产性或潜伏感染的潜力。对于任何一种结果,HSV-1必须抑制固有的免疫反应,调节病毒基因表达,并去除可能限制病毒过程的宿主蛋白。感染细胞蛋白0(ICP0),病毒编码的E3泛素连接酶,通过介导泛素转移到靶蛋白以改变它们的位置来支持这些过程,改变他们的功能,或者诱导它们退化。为了确定感觉神经元生产性感染过程中ICP0的泛素化靶标,我们免疫沉淀了感染HSV-1KOS(野生型)的原代成人感觉神经元的泛素化蛋白,HSV-1n212(表达截短,有缺陷的ICP0),和未感染的对照使用抗泛素抗体FK2(识别K29,K48,K63和单泛素化蛋白),随后进行LC-MS/MS和比较分析。我们鉴定出40种通过ICP0泛素化的独特蛋白质和17种通过ICP0和宿主机制泛素化的独特蛋白质。选择其中的高迁移率族蛋白I/Y(HMGI/Y)和TARDNA结合蛋白43(TDP43)用于进一步分析。我们显示ICP0泛素化HMGI/Y和TDP43,在生产性HSV-1感染期间的特定时间点改变蛋白质表达,证明ICP0以时间依赖性方式操纵感觉神经元环境以调节神经元的感染结果。