| 1 | Architectural proteins for the formation and maintenance of the 3D genome显示文摘Eukaryotic genomes are densely packaged into hierarchical three-dimensional(3D) structures that contain information about gene regulation and many other biological processes. With the development of imaging and sequencing-based technologies, 3D genome studies have revealed that the high-order chromatin structure is composed of hierarchical levels, including chromosome territories, A/B compartments, topologically associated domains, and chromatin loops. However, how this chromatin architecture is formed and maintained is not completely clear. In this review, we introduce experimental methods to investigate the 3D genome, review major architectural proteins that regulate 3D chromatin organization in mammalian cells, such as CTCF(CCCTC-binding factor), cohesin, lamins, and transcription factors, and discuss relevant mechanisms such as phase separation. | Mengfan Li Jingbo Gan Yuao Sun Zihan Xu Junsheng Yang Yujie Sun Cheng Li | 2020 | Science China(Life Sciences)2020，63，6： | 7 |
| 2 | PN-ImTLSM facilitates high-throughput low background single-molecule localization microscopy deep in the cell显示文摘When imaging the nucleus structure of a cell,the out-of-focus fluorescence acts as background and hinders the detection of weak signals.Light-sheet fluorescence microscopy(LSFM)is a wide-field imaging approach which has the best of both background removal and imaging speed.However,the commonly adopted orthogonal excitation/detection scheme is hard to be applied to single-cell imaging due to steric hindrance.For LSFMs capable of high spatiotemporal single-cell imaging,the complex instrument design and operation largely limit their throughput of data collection.Here,we propose an approach for high-throughput background-free fluorescence imaging of single cells facilitated by the Im-mersion Tilted Light Sheet Microscopy(ImTLSM).ImTLSM is based on a light-sheet projected off the optical axis of a water immersion objective.With the illumination objective and the detection objective placed opposingly,ImTLSM can rapidly patrol and optically section multiple individual cells while maintaining single-molecule detection sensitivity and resolution.Further,the simplicity and robustness of ImTLSM in operation and maintenance enables high-throughput image collection to establish background removal datasets for deep learning.Using a deep learning model to train the mapping from epi-illumination images to ImTLSM illumination images,namely PN-ImTLSM,we demonstrated crossmodality fluorescence imaging,transforming the epi-illumination image to approach the background removal performance obtained with ImTLSM.We demonstrated that PN-ImTLSM can be generalized to large-field homogeneous illumination imaging,thereby further improving the imaging throughput.In addition,compared to commonly used background removal methods,PN-ImTLSM showed much better performance for areas where the background intensity changes sharply in space,facilitating high-density single-molecule localization microscopy.In summary,PN-ImTLSM paves the way for background-free fluorescence imaging on ordinary inverted microscopes. | Boxin Xue Caiwei Zhou YizhiQin Yongzheng Li Yuao Sun Lei Chang Shipeng Shao Yongliang Li Mengling Zhang Chaoying Sun Renxi He Qian Peter Su Yujie Sun | 2021 | Biophysics Reports2021，7，4： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员