Biophysical Society Conference | Estes Park 2023

Membrane Budding and Fusion

Poster Abstracts

44-POS Board 15 SUPER-RESOLUTION IMAGING OF VOLTAGES IN THE INTERIOR OF INDIVIDUAL, VITAL MITOCHONDRIA

Peter J. Burke ; Shawn Lee 1 ; Douglas Wallace 2 ; 1 University of California, EECS, BME, Irvine, CA, USA 2 CHOP, Pathology, Philadelphia, PA, USA

We present super-resolution microscopy of functional, isolated mitochondria, enabling real-time studies of structure and function (voltages) in response to pharmacological manipulation. Changes in mitochondrial membrane potential as a function of time and position can be imaged in different metabolic states (not possible in whole cells), created by the addition of substrates and inhibitors of the electron transport chain, enabled by the isolation of vital mitochondria. By careful analysis of structure dyes and voltage dyes (lipophilic cations), we demonstrate that most of the fluorescent signal seen from voltage dyes is due to membrane bound dyes, and develop a model for the membrane potential dependence of the fluorescence contrast for the case of superresolution imaging, and how it relates to membrane potential. This permits direct analysis of mitochondrial structure and function (voltage) of isolated, individual mitochondria as well as submitochondrial structures in the functional, intact state, a major advance in super-resolution studies of living organelles.

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