Zhang Miaomiao, Guan Yong, Dang Zheng, Zhang Pinggen, Zheng Zhen, Chen Liang, Kuang Wen, Wang Chenchen, Liang Gaolin
Hefei National Laboratory of Physical Sciences at Microscale, Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China.
National Synchrotron Radiation Laboratory, University of Science and Technology of China, 42 Hezuohua South Road, Hefei, Anhui 230029, China.
Sci Adv. 2020 Oct 23;6(43). doi: 10.1126/sciadv.aba3190. Print 2020 Oct.
Directly observing intracellular nanostructure formation remains challenging. In this work, using a rationally designed small-molecule 4-nitrobenzyl carbamate-Cys(SEt)-Asp-Asp-Phe(iodine)-2-cyano-benzothiazole (NBC-Iod-CBT), we directly observed intracellular nanoparticle formation with nanocomputed tomography (nano-CT). In vitro, upon glutathione reduction and nitroreductase (NTR) cleavage, NBC-Iod-CBT undergoes a CBT-Cys click condensation reaction to self-assemble nanoparticles Iod-CBT-NPs with an average linear absorption coefficient (LAC) value of 0.182 ± 0.078 μm to x-ray. Nano-CT imaging of the NBC-Iod-CBT-treated, NTR-overexpressing HeLa cells showed the existence of Iod-CBT-NPs in their cytoplasm with an average LAC value of 0.172 ± 0.032 μm We anticipate that our strategy could help people to deeply understand the formation mechanism of intracellular nanostructures in the near future.
直接观察细胞内纳米结构的形成仍然具有挑战性。在这项工作中，我们使用合理设计的小分子4-硝基苄基氨基甲酸酯-Cys(SEt)-Asp-Asp-Phe(碘)-2-氰基苯并噻唑（NBC-碘-CBT），通过纳米计算机断层扫描（nano-CT）直接观察细胞内纳米颗粒的形成。在体外，经谷胱甘肽还原和硝基还原酶（NTR）切割后，NBC-碘-CBT发生CBT-Cys点击缩合反应，自组装形成纳米颗粒碘-CBT-NPs，其对X射线的平均线性吸收系数（LAC）值为0.182±0.078μm。对经NBC-碘-CBT处理、过表达NTR的HeLa细胞进行的nano-CT成像显示，其细胞质中存在碘-CBT-NPs，平均LAC值为0.172±0.032μm。我们预计，我们的策略在不久的将来能够帮助人们深入了解细胞内纳米结构的形成机制。
