A New Ultradian Rhythm Linked to Protein Degradation and Synthesis in Mammalian Cells

Ghenim, L.; Allier, C.; Obeid, P.; Herve, L.; Fortin, J.-Y.; Maxim, B.; Gidrol, X.

doi:10.1101/2019.12.20.882811

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bioRxiv · 10.1101/2019.12.20.882811

A New Ultradian Rhythm Linked to Protein Degradation and Synthesis in Mammalian Cells

Ghenim, L.·Allier, C.·Obeid, P.·Herve, L.·Fortin, J.-Y.·Maxim, B.·Gidrol, X.

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Abstract

We describe a new ultradian rhythm that occurs during the interphase of the cell cycle in a wide range of mammalian cells, including both primary and transformed cells. The rhythm was detected by holographic lens-free microscopy that follows the individual histories of the dry mass of thousands of live cells simultaneously, each at a resolution of five minutes. Importantly, the rhythm was observed in inherently heterogeneous cell populations, thus eliminating synchronization and labeling bias. The rhythm is independent of circadian rhythm, has a period of 4 hours and is temperature-compensated. We demonstrated that the 4 hr rhythm is suppressed by proteostasis disruptors and is detected only in proliferating cells, suggesting that it represents the periodic dynamics of protein mass in growing cells. Brief teaserWe have revealed a 4 hr rhythm in cell dry mass dynamics that seems to be general in proliferating mammalian cells.

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Ghenim, L., Allier, C., Obeid, P., Herve, L., Fortin, J.-Y., Maxim, B., Gidrol, X.. 2019-12-20. A New Ultradian Rhythm Linked to Protein Degradation and Synthesis in Mammalian Cells. https://doi.org/10.1101/2019.12.20.882811

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