Exogenous chromosomes reveal how sequence composition drives chromatin assembly, activity, folding and compartmentalization

Chapard, C.; Meneu, L.; Serizay, J.; Routhier, E.; Ruault, M.; Bignaud, A.; Gourgues, G.; Lartigue, C.; Piazza, A.; Taddei, A.; Beckouet, F.; Mozziconacci, J.; Koszul, R.

doi:10.1101/2022.12.21.520625

bioRxiv · 10.1101/2022.12.21.520625

Exogenous chromosomes reveal how sequence composition drives chromatin assembly, activity, folding and compartmentalization

Chapard, C.·Meneu, L.·Serizay, J.·Routhier, E.·Ruault, M.·Bignaud, A.·Gourgues, G.·Lartigue, C.·Piazza, A.·Taddei, A.·Beckouet, F.·Mozziconacci, J.·Koszul, R.

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Abstract

Genomic sequences co-evolve with DNA-associated proteins to ensure the multiscale folding of long DNA molecules into functional chromosomes. In eukaryotes, different molecular complexes organize the chromosomes hierarchical structure, ranging from nucleosomes and cohesin- mediated DNA loops to large scale chromatin compartments. To explore the relationships between the DNA sequence composition and the spontaneous loading and activity of these DNA-associated complexes in the absence of co-evolution, we characterized chromatin assembly and activity in yeast strains carrying exogenous bacterial chromosomes that diverged from eukaryotic sequences over 1.5 billion years ago. We show that nucleosome assembly, transcriptional activity, cohesin-mediated looping, and chromatin compartmentalization can occur in a bacterial chromosome with a largely divergent sequence integrated in a eukaryotic host, and that the chromatinization of bacterial chromosomes is highly correlated with their sequence composition. These results are a step forward in understanding how foreign sequences are interpreted by a host nuclear machinery during natural horizontal gene transfers, as well as in synthetic genomics projects.

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Chapard, C., Meneu, L., Serizay, J., Routhier, E., Ruault, M., Bignaud, A., Gourgues, G., Lartigue, C., Piazza, A., Taddei, A., Beckouet, F., Mozziconacci, J., Koszul, R.. 2022-12-21. Exogenous chromosomes reveal how sequence composition drives chromatin assembly, activity, folding and compartmentalization. https://doi.org/10.1101/2022.12.21.520625

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