DOES THE GENOME DETERMINE THE SIZE OF A VIRUS? - STUDYING VIRAL RNA IN SOLUTIONS

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 该提案概述了我们需要使用小角X射线散射方法研究病毒RNA。特别是，我们专注于相对较好地表征植物病毒（CCMV和BMV），并概述了SAXS实验，这将有助于阐明的力量管理自组装和组织的基因组物质（RNA在这种情况下）内的病毒衣壳。通过将溶液中病毒RNA的形状和大小与各种非病毒RNA（例如，信使，核糖体和随机）相同长度的RNA，我们希望验证第一种情况下的二级/三级结构是否与其他情况下的二级/三级结构根本不同。此外，我们想确定这些生物聚合物对离子环境变化的敏感程度。具体而言，在生理盐条件下，构象的变化与蛋白质衣壳呈现的内部体积限制相关。我们希望这些研究将最终引导我们回答更微妙的问题，例如：a）病毒RNA中的核苷酸序列是否明确编码有助于包装的特殊二级和三级结构，以及B）对于给定的衣壳蛋白，RNA的序列和长度是否因此控制组装颗粒的优选大小（T数）。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This proposal outlines our need for studying viral RNA using small-angle x-ray scattering methods. In particular we focus on relatively well characterized plant viruses (CCMV and BMV), and outline SAXS experiments that would help elucidate the forces governing self-assembly and organization of genomic material (RNA in this case) inside the viral capsid. By comparing the shape and size of the viral RNA in solution with those of various non-viral (e.g., messenger, ribosomal and random) RNAs of the same length, we hope to verify if the secondary/tertiary structure in the first case is fundamentally different from that of the others. Further, we would like to determine how sensitive these biopolymers are to changes in ionic environment. Specifically, under physiological salt conditions, do the changes in conformation correlate with the internal volume restrictions presented by a protein capsid. We hope these studies will eventually lead us towards answering more subtle questions such as: a) does the sequence of nucleotides in viral RNA explicitly code for a special secondary and tertiary structure conducive to packaging, and b) for a given capsid protein, do the sequence and length of RNA therefore control the preferred size (T-number) of the assembled particle over others.