Abstract
The ring-shaped cohesin complex regulates transcription, DNA repair, and chromosome segregation by dynamically entrapping chromosomes to promote chromosome compaction and sister-chromatid cohesion. The cohesin ring needs to open and close to allow its loading to and release from chromosomes. Cohesin dynamics are controlled by the releasing factors Pds5 and Wapl and the cohesin stabilizer Sororin. Here, we report the crystal structure of human Pds5B bound to a conserved peptide motif found in both Wapl and Sororin. Our structure establishes the basis for how Wapl and Sororin antagonistically influence cohesin dynamics. The structure further reveals that Pds5 can bind inositol hexakisphosphate (IP6). The IP6-binding segment of Pds5B is shaped like the jaw of a plier lever and inhibits the binding of Scc1 to Smc3. We propose that Pds5 stabilizes a transient, open state of cohesin to promote its release from chromosomes. The cohesin ring entraps DNA and regulates diverse chromosome processes, including chromosome segregation, transcription, and DNA repair. Pds5 is a critical cohesin regulator. Ouyang et al. report structural and functional analyses of human Pds5 and identify IP6 as an unanticipated cofactor in cohesin dynamics.
Original language | English (US) |
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Pages (from-to) | 248-259 |
Number of pages | 12 |
Journal | Molecular cell |
Volume | 62 |
Issue number | 2 |
DOIs | |
State | Published - Apr 21 2016 |
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology