A549 cells contain enlarged mitochondria with independently functional clustered mtDNA nucleoids
Fig 5
Swollen mitochondria exhibit a more oxidative enviroment than mitochondria with normal morphology.
A. Representative confocal image of the ROS signal generated by MitoSOX (red) accumulating in A549 cells expressing MLS-EGFP (green). Scale bars are 5 μm. Leica SP8, 63x, 5% CO2, 37⁰C, 95% relative humidity, operating in photon-counting mode. B. Trace derived from “Line-1” in A that intersects both normal and bloated mitochondria. Line is 20 μm and traces extend from left to right. C. Confocal image representing the oxidation state of mito-roGFP in A549 cells. The 525 nm emission intensity signals induced by 405 nm or 488 nm excitation, represent oxidized and reduced protein, respectively, are superimposed in the main panel and resolved individually in panels directly below. Scale bars are 10 μm. Leica SP8, 63x, 5% CO2, 37⁰C, 95% relative humidity, operating in photon-counting mode. D. Linear traces show the 525 nm fluorescence intensities for the oxidized (red) and reduced (green) forms of mito-roGFP2 in ROIs 1 and 2 of panel C bisecting normal and bloated mitochondria, respectively. E. Two-dimensional heatmap of the oxidized:reduced ratio of mito-roGFP.