Rivera-Fuentes Pablo, Wrobel Alexandra T, Zastrow Melissa L, Khan Mustafa, Georgiou John, Luyben Thomas T, Roder John C, Okamoto Kenichi, Lippard Stephen J
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139.
Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON, Canada M5G 1X5.
Chem Sci. 2015;6(3):1944-1948. doi: 10.1039/C4SC03388D.
Imaging mobile zinc in acidic environments remains challenging because most small-molecule optical probes display pH-dependent fluorescence. Here we report a reaction-based sensor that detects mobile zinc unambiguously at low pH. The sensor responds reversibly and with a large dynamic range to exogenously applied Zn in lysosomes of HeLa cells, endogenous Zn in insulin granules of MIN6 cells, and zinc-rich mossy fiber boutons in hippocampal tissue from mice. This long-wavelength probe is compatible with the green-fluorescent protein, enabling multicolor imaging, and facilitates visualization of mossy fiber boutons at depths of >100 µm, as demonstrated by studies in live tissue employing two-photon microscopy.
在酸性环境中对移动锌进行成像仍然具有挑战性，因为大多数小分子光学探针都表现出pH依赖性荧光。在此，我们报告了一种基于反应的传感器，它能够在低pH值下明确检测移动锌。该传感器对HeLa细胞溶酶体中外源施加的锌、MIN6细胞胰岛素颗粒中的内源性锌以及小鼠海马组织中富含锌的苔藓纤维终扣具有可逆响应，且动态范围大。这种长波长探针与绿色荧光蛋白兼容，可实现多色成像，并有助于在深度大于100 µm处可视化苔藓纤维终扣，这在使用双光子显微镜的活组织研究中得到了证明。
