High-Resolution Mapping of the Spatial Organization of a Bacterial Chromosome

Chromosomes must be highly compacted and organized within cells, but how this is achieved in vivo remains poorly understood. We report the use of chromosome conformation capture coupled with deep sequencing (Hi-C) to map the structure of bacterial chromosomes. Analysis of Hi-C data and polymer model...

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Bibliographic Details
Main Authors: Imakaev, Maksim Viktorovich, Le, Tung, Mirny, Leonid A, Laub, Michael T
Other Authors: Massachusetts Institute of Technology. Institute for Medical Engineering & Science
Format: Article
Language:en_US
Published: American Association for the Advancement of Science (AAAS) 2014
Online Access:http://hdl.handle.net/1721.1/86053
https://orcid.org/0000-0003-4764-8851
https://orcid.org/0000-0002-0785-5410
https://orcid.org/0000-0002-8288-7607
https://orcid.org/0000-0002-5320-2728
Description
Summary:Chromosomes must be highly compacted and organized within cells, but how this is achieved in vivo remains poorly understood. We report the use of chromosome conformation capture coupled with deep sequencing (Hi-C) to map the structure of bacterial chromosomes. Analysis of Hi-C data and polymer modeling indicates that the Caulobacter crescentus chromosome consists of multiple, largely independent spatial domains that are probably composed of supercoiled plectonemes arrayed into a bottle brush–like fiber. These domains are stable throughout the cell cycle and are reestablished concomitantly with DNA replication. We provide evidence that domain boundaries are established by highly expressed genes and the formation of plectoneme-free regions, whereas the histone-like protein HU and SMC (structural maintenance of chromosomes) promote short-range compaction and the colinearity of chromosomal arms, respectively. Collectively, our results reveal general principles for the organization and structure of chromosomes in vivo.