SEGMENTATION SOFTWARE FOR CRYOEM

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 在使用电子显微镜确定细胞机械的分子结构时，关键的一步是能够在三维密度图中识别单个分子。这些分子紧密地堆积在一起，使得它们的边界很难辨别。分割是确定不同分子密度图区域的过程。我们已经为UCSF Chimera开发了一个名为Segger的插件，它使用基于分水岭算法的自动计算来分割地图，并允许手动编辑结果，以修复在预期结构的额外专家知识指导下不可避免的错误。重点放在用单粒子电子冷冻显微镜研究孤立分子组件的电子显微镜上，人们对扩展该软件的兴趣浓厚，该软件还能够分割拥挤的细胞环境，其中大量不同的分子组件堆积在一起。

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. A key step in determining the molecular architecture of cellular machinery using electron microscopy is being able to identify the individual molecules in 3-dimensional density maps. The molecules are tightly packed together making their boundaries hard to discern. Segmentation is the process of determining the regions of density maps for different molecules. We have developed a plug-in to UCSF Chimera called Segger that segments maps using automated computations based on the watershed algorithm, and allows hand-editing of the results to fix the inevitable mistakes guided by additional expert knowledge of the expected structures. The focus has been on electron microscopy of isolated molecular assemblies studied by single-particle electron cryo-microscopy, and there is strong interest in extending the software also be able to segment crowded cellular environments where a large number of diverse molecular assemblies are packed together.