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Bacillus subtilis SMC complexes juxtapose chromosome arms as they travel from origin to terminus

ABSTRACT: Structural maintenance of chromosomes (SMC) complexes play critical roles in chromosome dynamics in virtually all organisms but how they function remains poorly understood. In Bacillus subtilis, SMC condensin complexes are topologically loaded at centromeric sites adjacent to the replication origin. Here we provide evidence that these ring-shaped assemblies tether the left and right chromosome arms together while traveling from the origin to the terminus (>2 Mb) at rates >50kb/min. Condensin movement scales linearly with time arguing for an active transport mechanism. These data support a model in which SMC complexes function by processively enlarging DNA loops. Loop formation followed by processive enlargement provides a mechanism for how condensin complexes compact and resolve sister chromatids in mitosis and how cohesin generates topologically associating domains (TADs) during interphase.

ORGANISM(S): Bacillus subtilis PY79

PROVIDER: GSE85612 | GEO | 2017/02/03

SECONDARY ACCESSION(S): PRJNA338948

REPOSITORIES: GEO

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