Actin Dynamics Affects Glycolytic Fluxes in a Single Cell

Living systems exist far from equilibrium, constantly consuming energy in order to maintain themselves. How this energy is dependent on and regulated by the various processes that a cell needs to stay alive is not very well understood. Here, we study glycolysis, a major energy production pathway in eukaryotic cells, and aim to quantify the fluxes associated with it. Using a recently developed fluorescent reporter whose signal is proportional to the concentration of a key glycolytic intermediate, we study meiosis in the egg cell of the bat star, Patiria miniata, with high spatiotemporal accuracy. Surprisingly, we observe an increase in the signal towards the boundaries of the cell, which persists throughout meiosis. Furthermore, we show that this signal is highly correlated with actin activity - by depolymerizing actomyosin networks, the heightened signal at the boundaries disappear. This provides evidence of feedback between actin activity and the metabolic flux inside a cell giving insights into how metabolism may be regulated by subcellular structures not directly associated with the biochemistry of metabolism. The existence of such feedback would help shape how we think about cellular energy production - going beyond a homogenous picture, to one where energy fluxes are dependent on the local chemical and physical environment.