Condensin but not cohesin SMC heterodimer induces DNA reannealing through protein–protein assembly

AUTOR(ES)

Sakai, Akiko

FONTE

Oxford University Press

RESUMO

Condensin and cohesin are chromosomal protein complexes required for chromosome condensation and sister chromatid cohesion, respectively. They commonly contain the SMC (structural maintenance of chromosomes) subunits consisting of a long coiled-coil with the terminal globular domains and the central hinge. Condensin and cohesin holo-complexes contain three and two non-SMC subunits, respectively. In this study, DNA interaction with cohesin and condensin complexes purified from fission yeast was investigated. The DNA reannealing activity is strong for condensin SMC heterodimer but weak for holo-condensin, whereas no annealing activity is found for cohesin heterodimer SMC and Rad21-bound heterotrimer complexes. One set of globular domains of the same condensin SMC is essential for the DNA reannealing activity. In addition, the coiled-coil and hinge region of another SMC are needed. Atomic force microscopy discloses the molecular events of DNA reannealing. SMC assembly that occurs on reannealing DNA seems to be a necessary intermediary step. SMC is eliminated from the completed double-stranded DNA. The ability of heterodimeric SMC to reanneal DNA may be regulated in vivo possibly through the non-SMC heterotrimeric complex.

Documentos Relacionados

• Cohesin release is required for sister chromatid resolution, but not for condensin-mediated compaction, at the onset of mitosis
• Protein-protein diffusional encounter.
• XRCC1 coordinates the initial and late stages of DNA abasic site repair through protein–protein interactions
• Annotation Transfer Between Genomes: Protein–Protein Interologs and Protein–DNA Regulogs
• Protein–Protein Interactions Governing Septin Heteropentamer Assembly and Septin Filament Organization in Saccharomyces cerevisiae