Defined chromosome structure in the genome-reduced bacterium Mycoplasma pneumoniae

作者：Trussart Marie; Yus Eva; Martinez Sira; Bau Davide; Tahara Yuhei O; Pengo Thomas; Widjaja Michael; Kretschmer Simon; Swoger Jim; Djordjevic Steven; Turnbull Lynne; Whitchurch Cynthia; Miyata Makoto; Marti Renom Marc A; Lluch Senar Maria; Serrano Luis

来源：Nature Communications, 2017, 8(1): 14665.

DOI：10.1038/ncomms14665

DNA-binding proteins are central regulators of chromosome organization; however, in genome-reduced bacteria their diversity is largely diminished. Whether the chromosomes of such bacteria adopt defined three-dimensional structures remains unexplored. Here we combine Hi-C and super-resolution microscopy to determine the structure of the Mycoplasma pneumoniae chromosome at a 10 kb resolution. We find a defined structure, with a global symmetry between two arms that connect opposite poles, one bearing the chromosomal Ori and the other the midpoint. Analysis of local structures at a 3 kb resolution indicates that the chromosome is organized into domains ranging from 15 to 33 kb. We provide evidence that genes within the same domain tend to be co-regulated, suggesting that chromosome organization influences transcriptional regulation, and that supercoiling regulates local organization. This study extends the current understanding of bacterial genome organization and demonstrates that a defined chromosomal structure is a universal feature of living systems.

• 出版日期2017-3-8