Structure of the human cohesin inhibitor Wapl.Ouyang, Z., Zheng, G., Song, J., Borek, D.M., Otwinowski, Z., Brautigam, C.A., Tomchick, D.R., Rankin, S., Yu, H.
(2013) Proc.Natl.Acad.Sci.USA 110: 11355-11360
- PubMed: 23776203
- DOI: 10.1073/pnas.1304594110
- PubMed Abstract:
- Phosphorylation-enabled binding of SGO1-PP2A to cohesin protects sororin and centromeric cohesion during mitosis.
Liu, H.,Rankin, S.,Yu, H.
(2013) Nat.Cell Biol. 15: 40
Cohesin, along with positive regulators, establishes sister-chromatid cohesion by forming a ring to circle chromatin. The wings apart-like protein (Wapl) is a key negative regulator of cohesin and forms a complex with precocious dissociation of siste ...
Cohesin, along with positive regulators, establishes sister-chromatid cohesion by forming a ring to circle chromatin. The wings apart-like protein (Wapl) is a key negative regulator of cohesin and forms a complex with precocious dissociation of sisters protein 5 (Pds5) to promote cohesin release from chromatin. Here we report the crystal structure and functional characterization of human Wapl. Wapl contains a flexible, variable N-terminal region (Wapl-N) and a conserved C-terminal domain (Wapl-C) consisting of eight HEAT (Huntingtin, Elongation factor 3, A subunit, and target of rapamycin) repeats. Wapl-C folds into an elongated structure with two lobes. Structure-based mutagenesis maps the functional surface of Wapl-C to two distinct patches (I and II) on the N lobe and a localized patch (III) on the C lobe. Mutating critical patch I residues weaken Wapl binding to cohesin and diminish sister-chromatid resolution and cohesin release from mitotic chromosomes in human cells and Xenopus egg extracts. Surprisingly, patch III on the C lobe does not contribute to Wapl binding to cohesin or its known regulators. Although patch I mutations reduce Wapl binding to intact cohesin, they do not affect Wapl-Pds5 binding to the cohesin subcomplex of sister chromatid cohesion protein 1 (Scc1) and stromal antigen 2 (SA2) in vitro, which is instead mediated by Wapl-N. Thus, Wapl-N forms extensive interactions with Pds5 and Scc1-SA2. Wapl-C interacts with other cohesin subunits and possibly unknown effectors to trigger cohesin release from chromatin.
Howard Hughes Medical Institute, Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.