Electron cryo-microscopy (cryoEM) is used to determine structures of biological molecules, including multi-protein complexes. Maps at better than 3.0Å resolution are relatively straightforward to interpret since atomic models of proteins and nucleic acids can be built directly. Still, these resolutions are often difficult to achieve, and map quality frequently varies within a structure. This results in data that are challenging to interpret, especially when crystal structures or suitable homology models are not available. Recent advances in mass spectrometry techniques, computational methods and model building tools facilitate subunit/domain fitting into maps, elucidation of protein contacts, and de novo generation of atomic models. Here, we review techniques for map interpretation and provide examples from recent studies of multi-protein complexes.

中文翻译：

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解释多蛋白质复合物的中等分辨率冷冻电镜图。

电子冷冻显微镜 (cryoEM) 用于确定生物分子的结构，包括多蛋白复合物。由于可以直接构建蛋白质和核酸的原子模型，因此分辨率高于 3.0Å 的图解解释起来相对简单。尽管如此，这些分辨率通常难以实现，并且地图质量在结构内经常变化。这导致难以解释的数据，特别是当晶体结构或合适的同源模型不可用时。质谱技术、计算方法和模型构建工具的最新进展促进了亚基/域拟合到图谱、蛋白质接触的阐明和原子模型的从头生成。这里，