Title: Learning the statistical folding of bacterial chromosomes

Speaker: Prof. Chase Broedersz (Vrije Universiteit)

Abstract:

The order and variability of bacterial chromosome organization, contained within the distribution of chromosome conformations, remain unclear. In this talk, I will discuss a data-driven statistical mechanics approach to investigate chromosome organization in bacteria. Specifically, we develop a maximum entropy approach to extract single-cell 3D chromosome conformations from Hi-C experiments on the model organism Caulobacter crescentus. The predictive power of our model is validated by independent experiments. We find that on large genomic scales, organizational features are predominantly present along the long cell axis: chromosomal loci exhibit striking long-ranged two-point axial correlations, indicating emergent order. This organization is associated with large genomic clusters we term Super Domains (SuDs), whose existence we support with super-resolution microscopy. On smaller genomic scales, our model reveals chromosome extensions that correlate with transcriptional and loop extrusion activity. Finally, we quantify the information contained in chromosome organization that may guide cellular processes. Our approach can be extended to other species, providing a general strategy to resolve variability in single-cell chromosomal organization.

The event will be hybrid. It will take place in C4.1278 and information for the online format will be sent to the CSM mailing list.