PICORNAVIRAL 3A PROTEINS AND HOST PROTEIN SECRETION

描述：（改编自研究者摘要）：蛋白分泌 在脊髓灰质炎病毒（PV）感染的早期，宿主细胞的器官被抑制。 初步证据支持脊髓灰质炎病毒3A蛋白 特异性抑制内质网（ER） 和高尔基体通过阻止从ER的顺行交通。当细胞 感染了表达3A蛋白的突变PV，该3A蛋白不抑制 蛋白质分泌，分泌增加水平的IFN-b、IL-6和IL-8， MHC I类介导的抗原向CD 8 + CTL的呈递增加。因此，在本发明中， 3A的一个重要功能是限制细胞的抗病毒反应， 影响病毒的发病机制。在该提议中，描述了实验， 将研究3A干扰内质网-高尔基体的分子机制 交通其他小核糖核酸病毒3A和2B等位基因的能力调查 家族和血清型将进行测试之间的关系， 抑制宿主蛋白质分泌和这些蛋白质的致病潜力 病毒。具有不同程度的抑制宿主蛋白的能力的PV变体 将通过新的遗传筛选来选择分泌物。这些变体将 作为候选小核糖核酸病毒的病毒复制子 疫苗。表达PV受体的转基因小鼠将感染 包装的复制子抑制或不抑制宿主蛋白质分泌， 将使用特异性MHC四聚体定量CD 8 + CTL应答。是 预期该方法将允许调节抗原 通过基于小核糖核酸病毒的载体呈递给细胞免疫应答， 这对疫苗设计至关重要。

DESCRIPTION: (Adapted from the Investigator's abstract): The protein secretory apparatus of host cells is inhibited early in poliovirus (PV) infection. Preliminary evidence supports the hypothesis that poliovirus 3A protein specifically inhibits protein traffic between the endoplasmic reticulum (ER) and Golgi by preventing anterograde traffic from the ER. When cells are infected with mutant PV that expresses a 3A protein which does not inhibit protein secretion, increased levels of IFN-b, IL-6 and IL-8 are secreted and MHC class I-mediated presentation of antigens to CD8+ CTL is increased. Thus, an important function of 3A is to limit cellular antiviral responses, thereby affecting viral pathogenesis. In this proposal experiments are described which will investigate the molecular mechanism by which 3A disrupts ER-to-Golgi traffic. A survey of the ability of 3A and 2B alleles from other picornaviral families and serotypes will be performed to test the relationship between the inhibition of host protein secretion and the pathogenic potential of these viruses. PV variants with various degrees of ability to inhibit host protein secretion will be selected by a novel genetic screen. These variants will be characterized and reconstructed into viral replicons as candidate picornaviral vaccines. Transgenic mice that express the PV receptor will be infected with packaged replicons that do or do not inhibit host protein secretion and the CD8+ CTL response will be quantified using specific MHC tetramers. It is anticipated that this method will allow the regulation of the antigen presentation to the cellular immune response by picornaviral-based vectors, which could be crucial in vaccine design.