Molecular Recognition Research Center, Korea Institute of Science and Technology, 5 Hwarang-ro 14gil, Seongbuk-gu, Seoul, 02792, Republic of Korea.
Department of Biological Chemistry, KIST-School UST, 5 Hwarang-ro 14-gil, Seongbuk-gu, Seoul, 02792, Republic of Korea.
Chembiochem. 2018 May 18;19(10):1001-1005. doi: 10.1002/cbic.201800059. Epub 2018 Apr 23.
Glutathione (GSH) is one of major antioxidants inside cells that regulates oxidoreduction homeostasis. Recently, there have been extensive efforts to visualize GSH in live cells, but most of the probes available today are simple detection sensors and do not provide details of cellular localization. A new fluorescent probe (pcBD2-Cl), which is cell permeable and selectively reacts with GSH in situ, has been developed. The in situ GSH-labeled probe (pcBD2-GSH) exhibited quenches fluorescence, but subsequent binding to cellular abundant glutathione S-transferase (GST) recovers the fluorescence intensity, which makes it possible to image the GSH-GST complex in live cells. Interactions between probe and GST were confirmed by means of photo-crosslinking under intact live-cell conditions. Interestingly, isomers of chloro-functionalized 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) compounds behaved very distinctively inside the cells. Following co-staining imaging with MitoTracker and mitochondria fractionation upon lipopolysaccharide-mediated reactive oxygen species induction experiments showed that pcBD2-GSH accumulated in mitochondria. This is the first example of a live-cell imaging probe to visualize translocation of GSH from the cytosol to mitochondria.
谷胱甘肽 (GSH) 是细胞内主要的抗氧化剂之一，可调节氧化还原稳态。最近，人们已经在努力实现在活细胞中可视化 GSH，但目前大多数可用的探针都是简单的检测传感器，无法提供有关细胞定位的详细信息。已经开发出一种新的荧光探针 (pcBD2-Cl)，它可穿透细胞并原位选择性地与 GSH 反应。原位 GSH 标记探针 (pcBD2-GSH) 表现出荧光猝灭，但随后与细胞中丰富的谷胱甘肽 S-转移酶 (GST) 结合会恢复荧光强度，这使得可以在活细胞中对 GSH-GST 复合物进行成像。通过在完整的活细胞条件下进行光交联，证实了探针与 GST 之间的相互作用。有趣的是，氯功能化的 4,4-二氟-4-硼-3a,4a-二氮杂-s-茚满 (BODIPY) 化合物的异构体在细胞内的行为非常不同。在用脂多糖诱导活性氧产生实验进行共染色成像和线粒体分离后，显示 pcBD2-GSH 积累在线粒体中。这是首例可视化 GSH 从细胞质到线粒体易位的活细胞成像探针。
