Munich Institute of Biomedical Engineering, Department of Bioscience, TUM School of Natural Sciences and TUM School of Medicine, Technical University of Munich, Munich, Germany.
Institute for Synthetic Biomedicine, Helmholtz Munich, Neuherberg, Germany.
Nat Biotechnol. 2023 Dec;41(12):1734-1745. doi: 10.1038/s41587-023-01713-y. Epub 2023 Apr 17.
While genetically encoded reporters are common for fluorescence microscopy, equivalent multiplexable gene reporters for electron microscopy (EM) are still scarce. Here, by installing a variable number of fixation-stable metal-interacting moieties in the lumen of encapsulin nanocompartments of different sizes, we developed a suite of spherically symmetric and concentric barcodes (EMcapsulins) that are readable by standard EM techniques. Six classes of EMcapsulins could be automatically segmented and differentiated. The coding capacity was further increased by arranging several EMcapsulins into distinct patterns via a set of rigid spacers of variable length. Fluorescent EMcapsulins were expressed to monitor subcellular structures in light and EM. Neuronal expression in Drosophila and mouse brains enabled the automatic identification of genetically defined cells in EM. EMcapsulins are compatible with transmission EM, scanning EM and focused ion beam scanning EM. The expandable palette of genetically controlled EM-readable barcodes can augment anatomical EM images with multiplexed gene expression maps.
虽然遗传编码报告基因常用于荧光显微镜，但适用于电子显微镜（EM）的可多重检测的基因报告基因仍然稀缺。在这里，我们通过在不同大小的 encapsulin 纳米隔室的腔室内安装数量可变的固定稳定的金属相互作用部分，开发了一系列具有球形对称和同心条带的条码（EMcapsulins），可通过标准 EM 技术进行读取。可以自动对六类 EMcapsulins 进行分割和区分。通过使用一组具有可变长度的刚性间隔物将几个 EMcapsulins 排列成不同的模式，进一步增加了编码容量。荧光 EMcapsulins 的表达可用于在光镜和 EM 下监测亚细胞结构。在果蝇和小鼠大脑中的神经元表达使我们能够在 EM 中自动识别遗传定义的细胞。EMcapsulins 与透射 EM、扫描 EM 和聚焦离子束扫描 EM 兼容。可扩展的遗传控制的 EM 可读条码调色板可以为解剖学 EM 图像添加多重基因表达图谱。
