Spatial heterogeneity of the cytosol revealed by machine learning-based 3D particle tracking.
Spatial heterogeneity of the cytosol revealed by machine learning-based 3D particle tracking.
复制标题
基于机器学习的 3D 粒子跟踪揭示了细胞质的空间异质性。
DOI：
10.1091/mbc.e20-03-0210
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发表时间：
2020
影响因子：
3.3
通讯作者：
Gladfelter,AmyS
中科院分区：
文献类型：
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作者：
McLaughlin,GraceA;Langdon,ErinM;Crutchley,JohnM;Holt,LiamJ;Forest,MGregory;Newby,JayM;Gladfelter,AmyS
胞质溶胶的空间结构和物理性质还不清楚。由于其空间和时间的异质性，细胞质的物质状态的测量是具有挑战性的。基因编码的多聚体纳米颗粒（GEM）的最新发展开辟了在多蛋白复合物的长度尺度（20-60 nm）的胞质溶胶的研究。我们开发了一种图像分析管道，用于在大型多核真菌的背景下对GEM进行3D成像，其中有证据表明细胞质的核分裂周期和分支的功能区室化。我们应用神经网络来跟踪3D中的粒子，然后创建空间变化扩散率的定量可视化。使用这个管道来分析空间扩散模式，我们发现，有很大的变化，在性质的细胞质。我们检测到的区域，其中GEM显示特别低的扩散率在菌丝尖端和附近的一些核，表明在一个单一的细胞内的胞质溶胶的物理状态空间变化。此外，我们观察到显着的细胞到细胞的平均扩散率的变化。因此，胞质溶胶的物理性质在时间和空间上变化很大，并且可以是单个细胞内和群体间异质性的来源。
The spatial structure and physical properties of the cytosol are not well understood. Measurements of the material state of the cytosol are challenging due to its spatial and temporal heterogeneity. Recent development of genetically encoded multimeric nanoparticles (GEMs) has opened up study of the cytosol at the length scales of multiprotein complexes (20–60 nm). We developed an image analysis pipeline for 3D imaging of GEMs in the context of large, multinucleate fungi where there is evidence of functional compartmentalization of the cytosol for both the nuclear division cycle and branching. We applied a neural network to track particles in 3D and then created quantitative visualizations of spatially varying diffusivity. Using this pipeline to analyze spatial diffusivity patterns, we found that there is substantial variability in the properties of the cytosol. We detected zones where GEMs display especially low diffusivity at hyphal tips and near some nuclei, showing that the physical state of the cytosol varies spatially within a single cell. Additionally, we observed significant cell-to-cell variability in the average diffusivity of GEMs. Thus, the physical properties of the cytosol vary substantially in time and space and can be a source of heterogeneity within individual cells and across populations.