Stein Kassi T, Moon Sun Jin, Sikes Hadley D
Department of Chemical Engineering , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States.
ACS Synth Biol. 2018 Sep 21;7(9):2037-2044. doi: 10.1021/acssynbio.8b00174. Epub 2018 Aug 31.
Among reactive oxygen species (ROS), HO alone acts as a signaling molecule that promotes diverse phenotypes depending on the intracellular concentration. Mitochondria have been suggested as both sources and sinks of cellular HO, and mitochondrial dysfunction has been implicated in diseases such as cancer. A genetically encoded HO generator, d-amino acid oxidase (DAAO), was targeted to the mitochondria of human cells, and its utility in investigating cellular response to a range of HO doses over time was assessed. Organelle-specific peroxiredoxin dimerization and protein S-glutathionylation were measured as indicators of increased HO flux due to the activity of DAAO. Cell death was observed in a concentration- and time-dependent manner, and protein oxidation shifted in localization as the dose increased. This work presents the first systematic study of HO-specific perturbation of mitochondria in human cells, and it reveals a marked sensitivity of this organelle to increases in HO in comparison with prior studies that targeted the cytosol.
在活性氧（ROS）中，仅羟基自由基（HO）作为一种信号分子，根据细胞内浓度促进多种表型。线粒体被认为是细胞内HO的来源和汇集点，并且线粒体功能障碍与癌症等疾病有关。一种基因编码的HO发生器，即D-氨基酸氧化酶（DAAO），被靶向到人类细胞的线粒体，并评估了其在研究细胞随时间对一系列HO剂量的反应中的效用。测量细胞器特异性过氧化物酶体二聚化和蛋白质S-谷胱甘肽化，作为由于DAAO活性导致HO通量增加的指标。观察到细胞死亡呈浓度和时间依赖性，并且随着剂量增加，蛋白质氧化的定位发生变化。这项工作首次对人类细胞中线粒体的HO特异性扰动进行了系统研究，并且与之前针对细胞质的研究相比，揭示了该细胞器对HO增加的显著敏感性。
