Evidence for widespread cytoplasmic structuring into mesoscale condensates.
Evidence for widespread cytoplasmic structuring into mesoscale condensates.
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DOI：
10.1038/s41556-024-01363-5
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发表时间：
2024-02
影响因子：
21.3
通讯作者：
Felix C Keber;Thao Nguyen;Andrea Mariossi;C. Brangwynne;M. Wühr
中科院分区：
文献类型：
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作者：
Felix C Keber;Thao Nguyen;Andrea Mariossi;C. Brangwynne;M. Wühr
区隔化是真核生物生命的基本特征，可以通过膜结合细胞器（如线粒体）和无膜生物分子凝聚物（如核仁）实现。已知的生物分子凝聚物通常表现出类似液体的性质，并且通过显微镜在~1 μ m的尺度上可见（参考文献，）。它们大多是通过显微镜来研究的，检查选择的单个蛋白质。到目前为止，已知的生物分子凝聚物有几十种，它们具有多种功能，例如，在转录、RNA加工或信号传导的调节中，它们的功能失调会导致疾病。然而，目前尚不清楚生物分子凝聚物在细胞组织中的利用程度以及它们通常形成的长度尺度。在这里，我们通过定量蛋白质组学、过滤、大小排除和稀释实验，在全球范围内检测来自xenopusegg提取物的天然细胞质。这些实验表明，至少18%的蛋白质组被组织成~100 nm尺度的中尺度生物分子凝聚体，并且似乎通过RNA或凝胶化来稳定。我们通过衍射极限以下的成像，通过研究蛋白质渗透到具有确定孔径的多孔底物中，确定了中尺度尺寸。我们的研究结果表明，真核细胞质通过生物分子凝聚体广泛组织，但在令人惊讶的短长度尺度上。
Compartmentalization is an essential feature of eukaryotic life and is achieved both via membrane-bound organelles, such as mitochondria, and membrane-less biomolecular condensates, such as the nucleolus. Known biomolecular condensates typically exhibit liquid-like properties and are visualized by microscopy on the scale of ~1 µm (refs.,). They have been studied mostly by microscopy, examining select individual proteins. So far, several dozen biomolecular condensates are known, serving a multitude of functions, for example, in the regulation of transcription, RNA processing or signalling,, and their malfunction can cause diseases,. However, it remains unclear to what extent biomolecular condensates are utilized in cellular organization and at what length scale they typically form. Here we examine native cytoplasm fromXenopusegg extract on a global scale with quantitative proteomics, filtration, size exclusion and dilution experiments. These assays reveal that at least 18% of the proteome is organized into mesoscale biomolecular condensates at the scale of ~100 nm and appear to be stabilized by RNA or gelation. We confirmed mesoscale sizes via imaging below the diffraction limit by investigating protein permeation into porous substrates with defined pore sizes. Our results show that eukaryotic cytoplasm organizes extensively via biomolecular condensates, but at surprisingly short length scales.