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bioRxiv · 10.1101/2025.02.13.637960

The response of mitochondrial position to glucose stimulation in a model system of the pancreatic beta cell

Perez, L.·Ng, X. W.·Piston, D. W.·Mukherji, S.
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Abstract

The compartmentalization of eukaryotic cells into membrane-bound organelles with specific subcellular positioning enables precise spatial and temporal control of cellular functions. While functionally significant mitochondrial localization has been demonstrated in cells such as neurons, it remains unclear how general these cell principles are. Here, we examine the spatial organization of mitochondria within MIN6 pancreatic beta cells under variable glucose conditions. We observe glucose-dependent redistributions of mitochondria, favoring peripheral localization at elevated glucose levels when insulin secretion is also elevated. Our results, formalized into a stochastic model of mitochondrial trafficking, suggest that active mitochondrial transport along microtubules and calcium activity, but not ATP synthesis, are critical regulators of this redistribution. These results suggest that mitochondrial positioning may contribute to optimizing energy delivery in response to local demand, potentially representing a general regulatory mechanism across various cell types.

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Perez, L., Ng, X. W., Piston, D. W., Mukherji, S.. 2025-02-16. The response of mitochondrial position to glucose stimulation in a model system of the pancreatic beta cell. https://doi.org/10.1101/2025.02.13.637960

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