LAUSR

Membrane tension pores determine the organelles dynamics and function giving rise to physical observables during cell death process. While fluorescent organelle-targeted probes for specific chemical analytes are increasingly available, subcellular dynamic processes involving not only chemical but physicochemical and physical parameters are uncommon. Here we report a mitochondrial chemical probe, named RCN, rationally designed to monitor the osmotic effects during the transmembrane tension pore formation by using local mitochondrial polarity and a subcellular localization redistribution property of the probe. Utilizing fluorescence spectroscopy, high-resolution confocal imaging and spectrally-resolved confocal microscopy we provide a new correlation between mitochondrial dynamics and bleb vesicles formation with osmotic pressure stimuli in the cell, where the mitochondrial local polarity resulted to be drastically increased. The RCN provides a reliable protocol to assess the transmembrane pore formation driven osmotic pressure increments though local polarity variations, a more robust physicochemical parameter allowing to measure the health and decease status of the cell.