Icosahedral Virion Scaffolding Proteins

蛋白质和核酸组装成病毒涉及许多分子相互作用。通常情况下，组装依赖于支架蛋白。类似于建筑中使用的脚手架，这些蛋白质有助于组装，但在最终产品中没有发现。本研究的主要目的是利用微小病毒科，一类小的单链DNA病毒，阐明支架介导的病毒形态发生的分子机制。支架蛋白结构域的功能是通过构建在相关病毒之间的嵌合蛋白或含有特定结构域缺失的蛋白来阐明的。这些改变的蛋白质只执行自然功能的一个子集，从而在不同的阶段阻止病毒粒子的形态形成。通过分析这些改变的蛋白质的有害影响以及病毒如何变异以克服这些影响(第二点遗传分析)，出现了关于病毒形态发生的更详细的图景。除了支架蛋白，蛋白质与单链微病毒科DNA基因组的相互作用似乎影响组装的最后阶段。将结合遗传和结构方法(X射线结晶学)进一步阐明这一相对较新的现象。更广泛的影响：该项目包括在首席研究员实验室对研究生和本科生进行科学教育。此外，作为研究的一部分产生的病毒和宿主细胞株被用于由首席研究员讲授的大型本科微生物学课程，以说明经典遗传学和分子遗传学的概念。

The assembly of proteins and nucleic acids into viruses involves numerous molecular interactions. Often assembly is dependent on scaffolding proteins. Analogous to scaffoldings used in building construction, these proteins assist assembly, but are not found in the final product. The broad objective of this research is to elucidate the molecular mechanisms of scaffolding-mediated viral morphogenesis, using the Microviridae, a family of small single-stranded DNA viruses. The functions of scaffolding protein domains are elucidated with chimeric proteins, constructed between related viruses, or proteins containing a deletion of a specific domain. These altered proteins only perform a subset of the natural functions, thus arresting virion morphogenesis at distinct stages. By analyzing the deleterious effects of these altered proteins and how viruses can mutate to overcome these effects (second-site genetic analyses), a more detailed picture of viral morphogenesis emerges. In addition to scaffolding proteins, protein interactions with single-stranded Microviridae DNA genomes appear to affect the last stage of assembly. A combination of genetic and structural approaches (X-ray crystallography) will be used to further elucidate this relatively new phenomenon. Broader Impact: The project includes the scientific education of graduate and undergraduate students in the Principal Investigator's laboratory. In addition, viral and host cell strains generated as part of the research are used in a large undergraduate Microbiology course, taught by the Principal Investigator, to illustrate the concepts of both classical and molecular genetics.