MATURATION INTERMEDIATES OF A T=4 VIRUS CAPSID STUDIED BY TIME-RESOLVED X-RAY SC

通过时间分辨 X 射线 SC 研究 T=4 病毒衣壳的成熟中间体

• 批准号: 7954204
• 负责人: HIROTSUGU TSURUTA
• 金额: $ 0.25万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-03-01 至 2010-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7954204
• 关键词: Area; Caliber; Capsid; Computer Retrieval of Information on Scientific Projects Database; Data Quality; Funding; Grant; Institution; Kinetics; Manuals; Process; RNA; Research; Research Personnel; Resources; Roentgen Rays; Role; Series; Shapes; Source; Time Study; United States National Institutes of Health; Virus; Virus-like particle; data acquisition; detector; improved; instrumentation; research study; scaffold; structural biology; synchrotron radiation; time resolved data; virus morphology

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. Nudaurelia capensis omega virus-like particle, a T=4 virus capsid, undergoes a pH promoted maturation process. Using the much improved instrumentation on SSRL BL4-2 we have begun studying the kinetics of structural change associated with the maturation process. Prior to this effort, we detected a structural intermediate [Canady et al. J .Mol. Biol. 311, 803-814 (2001)], but the data quality achievable then did not permit us to analyze structural details. Very recent experiments demonstrate that a much smaller quantity of virus-like particle (VLP) is sufficient to obtain higher quality data due to the vastly improved instrumentation, in particular the improved detector sensitivity and larger 2D active area as well as the higher beam flux level. Performing manual mixing, followed by a series of time-resolved data acquisition (each 3 sec exposure), we have been able to isolate a structural intermediate at intermediary pH values between neutral (pH 7.6) and pH 5.0, which was used to promote the maturation in our earlier studies. The other important observation is that two VLPs with different RNA contents show slight different shape and diameter. This is the first direct experimental observation of the significant role of RNA scaffolding in virus morphology.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 Nudaurelia capensis omega 病毒样颗粒（T=4 病毒衣壳）经历 pH 促进的成熟过程。使用 SSRL BL4-2 上经过大幅改进的仪器，我们已经开始研究与成熟过程相关的结构变化动力学。在此之前，我们检测到了一种结构中间体 [Canady 等人。 J.摩尔。生物。 311, 803-814 (2001)]，但当时可达到的数据质量不允许我们分析结构细节。最近的实验表明，由于仪器的极大改进，特别是探测器灵敏度的提高、更大的二维活性区域以及更高的光束通量水平，更少数量的病毒样颗粒（VLP）就足以获得更高质量的数据。通过执行手动混合，然后进行一系列时间分辨数据采集（每次曝光 3 秒），我们能够在中性 (pH 7.6) 和 pH 5.0 之间的中间 pH 值下分离出结构中间体，这在我们早期的研究中用于促进成熟。另一个重要的观察结果是，具有不同 RNA 含量的两个 VLP 的形状和直径略有不同。这是首次直接实验观察RNA支架在病毒形态中的重要作用。