University of Rochester Medical Center, Department of Anesthesiology and Perioperative Medicine, 575 Elmwood Ave., Rochester, NY, 14642, Box 711/604, USA.
University of Rochester Medical Center, Department of Pharmacology and Physiology, 575 Elmwood Ave., Rochester, NY, 14642, Box 711/604, USA.
Nat Commun. 2023 Sep 27;14(1):6036. doi: 10.1038/s41467-023-41682-z.
Hydrogen peroxide (HO) functions as a second messenger to signal metabolic distress through highly compartmentalized production in mitochondria. The dynamics of reactive oxygen species (ROS) generation and diffusion between mitochondrial compartments and into the cytosol govern oxidative stress responses and pathology, though these processes remain poorly understood. Here, we couple the HO biosensor, HyPer7, with optogenetic stimulation of the ROS-generating protein KillerRed targeted into multiple mitochondrial microdomains. Single mitochondrial photogeneration of HO demonstrates the spatiotemporal dynamics of ROS diffusion and transient hyperfusion of mitochondria due to ROS. This transient hyperfusion phenotype required mitochondrial fusion but not fission machinery. Measurement of microdomain-specific HO diffusion kinetics reveals directionally selective diffusion through mitochondrial microdomains. All-optical generation and detection of physiologically-relevant concentrations of HO between mitochondrial compartments provide a map of mitochondrial HO diffusion dynamics in situ as a framework to understand the role of ROS in health and disease.
过氧化氢（HO）作为第二信使，通过在线粒体中高度分隔的方式产生来传递代谢压力的信号。活性氧（ROS）的产生和扩散的动力学在细胞器间以及进入细胞质，从而控制氧化应激反应和病理，但这些过程仍知之甚少。在这里，我们将 HO 生物传感器 HyPer7 与靶向多个线粒体微区的 ROS 生成蛋白 KillerRed 的光遗传学刺激相结合。HO 的单线粒体光生成证明了 ROS 扩散的时空动力学和由于 ROS 导致的线粒体瞬时融合。这种瞬时融合表型需要线粒体融合而不是分裂机制。测量微区特异性 HO 扩散动力学揭示了通过线粒体微区的定向选择扩散。细胞器间生理相关浓度的 HO 的全光学产生和检测提供了线粒体 HO 扩散动力学的原位图谱，作为理解 ROS 在健康和疾病中的作用的框架。
