elF4E - susceptibility factor for potyvirus infection with potential predictive resistance strategies

在这个项目中，我们想了解一种特殊的蛋白质，它帮助一些病毒感染植物。这种蛋白质，称为真核翻译起始因子4E，或eIF4 E，存在于高等生物的所有细胞中，并在通过阅读信使RNA（mRNA）产生其他蛋白质中发挥核心作用。我们发现，没有这种蛋白质的植物可以抵抗某些病毒的感染。虽然依赖这种蛋白质的特定病毒（马铃薯Y病毒）具有与mRNA结构略有不同的RNA，但我们认为eIF4E在帮助病毒RNA产生其他蛋白质方面起着非常相似的作用。从对马铃薯Y病毒属具有抗性的不同作物植物的研究中，我们知道存在不同形式的eIF4E，其不能帮助马铃薯Y病毒属感染。似乎这些抗性植物不能产生病毒蛋白与eIF4E不能结合病毒RNA的起始端有关。在我们对抗豌豆马铃薯Y病毒（称为豌豆种子传播花叶病毒：PSbMV）的豌豆的研究中，我们还鉴定了eIF4E的另一个非常令人惊讶的特性。它也有能力帮助PSbMV从一个细胞移动到另一个细胞，通过植物传播感染。因此，改变的eIF4E防止病毒在抗性豌豆植物中复制和传播。大分子的细胞间运动对植物生长和发育也很重要，尽管所涉及的机制通常知之甚少。因此，对eIF4E的研究可以告诉我们几个非常重要的生物学领域：病毒如何感染植物以及植物的抗性潜力，RNA翻译产生蛋白质，以及细胞与细胞之间的通讯。我们将在eIF4E蛋白中进行新的改变，并将这些改变与植物进行mRNA翻译、病毒复制和病毒在细胞间移动的潜力联系起来。我们还将确定elF4E和病毒蛋白的原子结构，它们在复合物中结合在一起。通过这种方式，我们将了解蛋白质是如何结合在一起的，以及我们需要做些什么来阻止它发生。从这些信息中，我们将确定突变豌豆植物的复合物不能形成，因此植物有潜力表现出新的抗PSbMV和其他马铃薯Y病毒。我们还将确定实验植物拟南芥的突变体，这将建立一系列遗传和生物学工具，以进一步解剖细胞间的通信。

In this project we want to understand a special protein that helps some viruses to infect plants. This protein, called eukaryotic translation initiation factor 4E, or elF4E, exists in all cells of higher organisms and plays a central role in producing other proteins by reading messenger RNA (mRNA). We showed that plants without this protein can be resistant to infection with some viruses. Although specific viruses (Potyviruses) that depend upon this protein have an RNA with a slightly different structure from that of mRNAs, we believe that elF4E plays a very similar role in helping the viral RNA to produce other proteins. From studies of different crop plants that are resistant to potyviruses, we know of the existence of different forms of elF4E which cannot assist potyvirus infection. It appears that the inability of these resistant plants to produce viral proteins is associated with a failure of elF4E to bind to the starting-end of the viral RNA. In our studies of peas resistant to pea potyvirus (called Pea seed-borne mosaic virus: PSbMV), we have also identified another very surprising property of elF4E. It also has the ability to assist PSbMV to move from one cell to another, to spread the infection through the plant. Hence, altered elF4E prevents the virus from both replicating and spreading in resistant pea plants. Cell-to-cell movement of large molecules is also important for plant growth and development although the mechanisms involved are generally very poorly understood. Therefore, the study of elF4E can tell us about several very important areas of biology: how viruses infect plants and the potential for resistance in plants, the translation of RNAs to produce proteins, and cell-to-cell communication. We will make new changes in the elF4E protein and relate these to the potential of plants to carry out mRNA translation, virus replication, and virus movement from cell to cell. We will also determine the atomic structure of the elF4E and virus proteins that join together in a complex. In this way we will understand how the proteins join together and what we need to do to stop it happening. From this information we will identify mutant pea plants where the complex cannot form and therefore plants with potential to exhibit new resistance to PSbMV and other potyviruses. We will also identify mutants for the experimental plant Arabidopsis, which will establish a range of genetic and biological tools for further dissection of cell-to-cell communications.