Temporal and spatial coordination of DNA segregation and cell division in an archaeon.

Parham, J.; Cezanne, A.; Sorichetti, V.; Hoogenberg, B.; Foo, S.; Kuo, Y.-w.; Mawdesley, E.; Gatward, L. D.; Schulze, U.; Boulanger, J.; Saric, A.; Baum, B.

doi:10.1101/2025.05.28.656325

bioRxiv · 10.1101/2025.05.28.656325

Temporal and spatial coordination of DNA segregation and cell division in an archaeon.

Parham, J.·Cezanne, A.·Sorichetti, V.·Hoogenberg, B.·Foo, S.·Kuo, Y.-w.·Mawdesley, E.·Gatward, L. D.·Schulze, U.·Boulanger, J.·Saric, A.·Baum, B.

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Abstract

Cells must coordinate DNA segregation with cytokinesis to ensure that each daughter cell inherits a complete genome. Here, we explore how DNA segregation and division are mechanistically coupled in archaeal relatives of eukaryotes, which lack CDK/Cyclins. Using live cell imaging we first describe the series of sequential changes in DNA organisation that accompany cell division in Sulfolobus, which computational modelling shows likely aid genome segregation. Through a perturbation analysis we identify a regulatory checkpoint which ensures that the compaction of the genome into two spatially segregated nucleoids only occurs once cells have assembly a division ring - which also defines the axis of DNA segregation. Finally, we show that DNA compaction and segregation depends, in part, on a ParA homologue, SegA, and its partner SegB, whose absence leads to bridging DNA. Taken together, these data show how regulatory checkpoints like those operating in eukaryotes aid high-fidelity division in an archaeon.

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Parham, J., Cezanne, A., Sorichetti, V., Hoogenberg, B., Foo, S., Kuo, Y.-w., Mawdesley, E., Gatward, L. D., Schulze, U., Boulanger, J., Saric, A., Baum, B.. 2025-05-29. Temporal and spatial coordination of DNA segregation and cell division in an archaeon.. https://doi.org/10.1101/2025.05.28.656325

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