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bioRxiv · 10.1101/2020.02.07.938985

Mitochondria dynamics in postmitotic cells drives neurogenesis through Sirtuin-dependent chromatin remodeling.

Abstract

The conversion of neural stem cells into neurons is associated with massive remodeling of organelles and chromatin, but whether and how these are linked to control neuronal fate commitment remains unknown. We examined and manipulated mitochondria dynamics with high temporal resolution during mouse and human cortical neurogenesis. We reveal that shortly after cortical stem cells have divided, daughter cells that retain high levels of mitochondria fission will become neurons, while those destined to self-renew undergo rapid mitochondria fusion. Induction of mitochondria fusion after mitosis redirects daughter cells towards cell self-renewal, but only during a restricted time window, which is doubled in human cortical stem cells with higher self-renewing potential. Mitochondria dynamics drives neurogenesis through modulation of the NAD+ sensor Sirtuin-1, leading to Histone deacetylation and chromatin remodeling necessary for neurogenic conversion. Our data reveal a post-mitotic critical period of neurogenesis, linking mitochondria state with cell fate.

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Iwata, R., Vanderhaeghen, P.. 2020-02-08. Mitochondria dynamics in postmitotic cells drives neurogenesis through Sirtuin-dependent chromatin remodeling.. https://doi.org/10.1101/2020.02.07.938985

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