Glycolytic oscillations in eukaryotic cells followed by NADH imaging

Monitoring intrinsic energy metabolism over long periods of time allows the study of cellular communication between cell populations. By using the metabolite NADH as an intrinsic marker for glycolysis, the dynamics of individual cells can be monitored and their interactions studied. Glucose consumption by glycolysis and alcoholic fermentation leads to the production of metabolites, some of which are released. Coupling between yeast cells depends on the release and sensing of the messenger acetaldehyde, which diffuses through the extracellular medium. Yeast cells are well known for the oscillatory behavior of the glycolysis and their metabolic organization. The exchange of messenger molecules can result in waves and synchronized patterns in which all cells oscillate in concert. Essential to this study is an ultrasensitive detection system that allows excitation of the weak fluorescence of NADH by low-intensity UV light.

(a) The time-series of the collective NADH fluorescence signal for a yeast population of cell density ρ=0.1%. Partial synchronisation of intracellular oscillations occurs at 760 s ≤t≤1100 s. (b) Development of the relative amplitudes of oscillations of each cell, and (c) of their phases. In (b) and (c) the cells are sorted according to their phases at time t=900 s. (d) Evolution of the distribution of instantaneous frequencies fi of the cells, and (e) of the distribution of the phase difference Δϕi between the phase ϕi of each individual cell to that of the average phase Φ of all cells of the population. (f) Time dependence of the order parameter R. The field of view had a diameter of 169 μm, and hosted 232 cells. Glucose was added to the cell suspension at t=−158 s.

[1] Weber, A., Zuschratter, W. & Hauser, M.J.B. Partial synchronisation of glycolytic oscillations in yeast cell populations. Sci Rep 10, 19714 (2020).

[2] Weber, A., Prokazov, Y., Zuschratter, W., Hauser, M.J.B. (2012) Desynchronisation of Glycolytic Oscillations in Yeast Cell Populations. PLOS ONE 7(9): e43276.