High resolution spatial investigation of intracellular oxygen in muscle cells

Abstract

ABSTRACTMolecular oxygen (O2) is one of the most functionally relevant metabolites. O2is essential for mito-chondrial aerobic respiration. Changes in O2affect muscle metabolism and play a critical role in the maintenance of skeletal muscle mass, with lack of sufficient O2resulting in detrimental loss of muscle mass and function. How exactly O2is used by muscle cells is less known, mainly due to the lack of tools to address O2dynamics at the cellular level. Here we discuss a new imaging method for the real time quantification of intracellular O2in muscle cells based on a genetically encoded O2-responsive sensor, Myoglobin-mCherry. We show that we can spatially resolve and quantify intracellular O2concentration in single muscle cells and that the spatiotemporal O2gradient measured by the sensor is linked to, and reflects, functional metabolic changes occurring during the process of muscle differentiation.HighlightsReal time quantitation of intracellular oxygen with spatial resolutionIdentification of metabolically active sites in single cellsOxygen metabolism is linked to muscle differentiation