Interphase chromosomes of the Aedes aegypti mosquito are liquid crystalline and can sense mechanical cues

Contessoto, V. G.; Dudchenko, O.; Aiden, E. L.; Wolynes, P. G.; Onuchic, J. N.; Di Pierro, M.

doi:10.1101/2022.02.01.478655

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bioRxiv · 10.1101/2022.02.01.478655

Interphase chromosomes of the Aedes aegypti mosquito are liquid crystalline and can sense mechanical cues

Contessoto, V. G.·Dudchenko, O.·Aiden, E. L.·Wolynes, P. G.·Onuchic, J. N.·Di Pierro, M.

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Abstract

We use data-driven physical simulations to study the three-dimensional architecture of the Aedes aegypti genome. Hi-C maps exhibit both a broad diagonal and compart-mentalization with telomeres and centromeres clustering together. Physical modeling reveals that these observations correspond to an ensemble of 3D chromosomal structures that are folded over and partially condensed. Clustering of the centromeres and telomeres near the nuclear lamina appears to be a necessary condition for the formation of the observed structures. Further analysis of the mechanical properties of the genome reveals that the chromosomes of Aedes aegypti, by virtue of their atypical structural organization, are highly sensitive to the deformation of the nuclei. This last finding provides a possible physical mechanism linking mechanical cues to gene regulation.

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Contessoto, V. G., Dudchenko, O., Aiden, E. L., Wolynes, P. G., Onuchic, J. N., Di Pierro, M.. 2022-02-03. Interphase chromosomes of the Aedes aegypti mosquito are liquid crystalline and can sense mechanical cues. https://doi.org/10.1101/2022.02.01.478655

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