Interplay between hepatitis C virus structural proteins and the p7 ion channel during particle assembly

目前有超过1.7亿人感染丙型肝炎病毒（HCV）;尽管大多数人并不知道他们是阳性的，因为最初的疾病非常轻微。然而，几十年后，症状出现，许多患者由于严重肝损伤（称为肝硬化，甚至肝癌）的发展而需要肝移植。在发达国家，药物组合可用于治疗这些患者，尽管这些药物组合仅在约50%的病例中起作用，并且具有严重的副作用。由于治疗失败，去年仅在美国就有1万人死于HCV感染。直到最近，研究人员还无法在实验室中培养HCV，这严重限制了开发抗感染新药的进展。然而，在2005年，发现了一种可以在培养物中生长的新病毒株。这意味着，人们首次可以研究单个病毒颗粒在细胞内形成的方式，为药物发现提供了一个新的领域。病毒颗粒由蛋白质外壳或核心组成，围绕着基因组，包括HCV在内的许多病毒颗粒都有第二个膜壳，称为包膜，其中包含允许病毒进入新细胞的蛋白质。在受感染的细胞内构建新的病毒颗粒是一个复杂的过程，因此病毒会劫持宿主细胞的机制来实现这一目标。病毒采用的一种策略是制造蛋白质，改变细胞内的环境，使其适合新病毒颗粒的组装。对于HCV，这种蛋白质被称为p7。我发现p7能够在细胞膜上形成七元孔，从而改变细胞各个部分的酸性。我的研究还表明，一种叫做金刚烷胺的药物可以阻止p7这样做。我的研究将测试像金刚烷胺这样的药物是否可以用来阻止HCV在培养中的传播，这是开发新的临床治疗方法的第一步。然后，我将研究这些孔在组装过程中如何影响其他颗粒成分，以及在细胞中发生这种情况。然后，我将使用荧光HCV在显微镜下跟踪颗粒离开活细胞时的路线。最后，我将确定HCV操纵细胞机器的哪些部分以产生新的颗粒，这可以突出未来药物开发的目标。

Over 170 million people currently live with hepatitis C virus (HCV); although most are not aware that they are positive as the initial illness is extremely mild. Decades later, however, symptoms appear and many patients require liver transplants due to the development of severe liver damage, known as cirrhosis, or even liver cancer. In developed countries, drug combinations can be used to treat these patients, although these only work in about 50% of cases and have severe side-effects. As a result of failed treatment, 10 000 individuals died from HCV infection last year in the USA alone.Until very recently, researchers have been unable to grow HCV in the laboratory, which has severely limited progress on developing new drugs to combat infection. In 2005, however, a new strain of the virus that could be grown in culture was discovered. This meant that for the first time, the way in which individual virus particles are made within the cell could be studied, providing a new area for drug discovery.Virus particles are made of a protein shell, or core, that surrounds the genome and many, including HCV, have a second membranous shell known as the envelope which contains proteins that allow the virus to enter new cells. The construction of a new particle within an infected cell is a complex process, so the virus hijacks host cell machinery to achieve it. One strategy the virus employs is to make proteins that alter the environment within the cell, making it suitable for the assembly of new virus particles. For HCV, this protein is known as p7. I discovered that p7 is able to form seven-membered pores in membranes, which alter how acidic various parts of the cell become. I also showed that a drug called amantadine can prevent p7 from doing this.My study will test whether drugs like amantadine can be used to stop HCV spreading in culture, which is the first step towards developing new clinical treatments. I will then investigate how these pores affect the other particle components during assembly and where in the cell this takes place. I will then use a fluorescent HCV to track, under the microscope, the route which particles take when leaving a live cell. Lastly, I will determine which parts of the cellular machinery HCV manipulates in order to create new particles, which could highlight targets for future drug development.