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Human Condensin I and II Drive Extensive ATP-Dependent Compaction of Nucleosome-Bound DNA.

ABSTRACT: Structural maintenance of chromosomes (SMC) complexes are essential for genome organization from bacteria to humans, but their mechanisms of action remain poorly understood. Here, we characterize human SMC complexes condensin I and II and unveil the architecture of the human condensin II complex, revealing two putative DNA-entrapment sites. Using single-molecule imaging, we demonstrate that both condensin I and II exhibit ATP-dependent motor activity and promote extensive and reversible compaction of double-stranded DNA. Nucleosomes are incorporated into DNA loops during compaction without being displaced from the DNA, indicating that condensin complexes can readily act upon nucleosome-bound DNA molecules. These observations shed light on critical processes involved in genome organization in human cells.

SUBMITTER: Kong M

PROVIDER: S-EPMC7335352 | biostudies-literature |

REPOSITORIES: biostudies-literature

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