Investigating the role of the E5 viroporin of human papillomavirus (HPV) in transformation and the virus life cycle

宫颈癌是全球主要的死亡原因，几乎普遍与人类乳头瘤病毒(HPV)感染有关。此外，HPV感染还与越来越多的其他癌症有关，这些癌症可以影响到两性；其中包括头颈癌。并不是所有感染HPV的人都会患上癌症，但人们认为，病毒产生的一些蛋白质构建块负责改变它们感染的细胞的性质，使它们最终可能发展为癌细胞。人乳头瘤病毒表达其中三种“癌蛋白”。在这三种蛋白质中，对E5蛋白的了解最少。这可能是由于这种蛋白质的困难性质使其难以研究。我们最近表明，E5能够形成环状结构，充当具有中心孔的通道，在人造膜上形成孔，我们可以用它来模拟细胞内部。据认为，这个小孔必须允许小分子和离子通过它，也许这会导致受感染细胞内环境的变化。我们使用基于计算机的通道模拟来设计可以阻断这个孔道的小分子，我们发现这些抑制剂也能够阻止细胞中E5的一些已知的S效应。现在我们想要进一步的研究，试图了解这个通道是如何工作的，是什么使它打开或关闭，以及我们是否可以建立更好的抑制剂来关闭它。此外，我们想知道该通道在细胞中的作用，以及病毒是否需要该通道来维持其生命周期。在这些研究中，我们将使用实验室中的细胞培养实验，重点关注在细胞中表达E5的一些众所周知的影响。这些研究应该会让我们清楚地了解E5通道是否对HPV的生命周期是必要的。如果是这样的话，这就开启了将这种蛋白质作为抗病毒治疗靶点的可能性。

Cervical cancer is a leading cause of death worldwide and is almost universally associated with infection with the human papillomavirus (HPV). In addition, HPV infection is also associated with an increasing number of other cancer that can affect both sexes; these include cancer of the head and neck. Not all people who are infected with HPV will develop cancer but it is thought that some of the protein building blocks produced by the virus are responsible for changing the nature of the cells that they infect so that they may eventually develop into cancerous cells. HPV expresses three of these "oncoproteins". Out of the three, the E5 protein is the least understood. This is probably due to the difficult nature of this protein that makes it hard to study.We have recently shown that E5 is able to form ring-like structures that act as a channel with a central pore that forms holes in artificial membranes that we can use to mimic the inside of cells. It is thought that this pore must allow small molecules and ions to pass through it, and perhaps this causes changes within the environment of the infected cell. We used computer based simulations of the channel to design small molecules that could block this pore and we found that these inhibitors were also able to prevent some of E5's known effects in cells.We now want to take this research further to try and understand how this channel works, what makes it open or close and can we build better inhibitors to switch it off. In addition, we want to know what the channel does in cells and whether the virus needs this channel for its life cycle. For these studies we will use cell culture experiments in the laboratory and focus on some well know effects of expressing E5 in cells.These studies should give us a clear picture of whether the E5 channel is essential for the HPV life cycle. If so then this opens up the possibility of targeting this protein for anti-viral therapeutics.