Cyclin A2 degradation during the spindle assembly checkpoint requires multiple binding modes to the APC/C

DOI: 10.1038/s41467-019-11833-2

Authors: Suyang Zhang (MRC Laboratory of Molecular Biology) , Thomas Tischer (MRC Laboratory of Molecular Biology) , David Barford (MRC Laboratory of Molecular Biology)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nature Communications , VOL 10

State: Published (Approved)
Published: August 2019
Diamond Proposal Number(s): 17434

Abstract: The anaphase-promoting complex/cyclosome (APC/C) orchestrates cell cycle progression by controlling the temporal degradation of specific cell cycle regulators. Although cyclin A2 and cyclin B1 are both targeted for degradation by the APC/C, during the spindle assembly checkpoint (SAC), the mitotic checkpoint complex (MCC) represses APC/C's activity towards cyclin B1, but not cyclin A2. Through structural, biochemical and in vivo analysis, we identify a non-canonical D box (D2) that is critical for cyclin A2 ubiquitination in vitro and degradation in vivo. During the SAC, cyclin A2 is ubiquitinated by the repressed APC/C-MCC, mediated by the cooperative engagement of its KEN and D2 boxes, ABBA motif, and the cofactor Cks. Once the SAC is satisfied, cyclin A2 binds APC/C-Cdc20 through two mutually exclusive binding modes, resulting in differential ubiquitination efficiency. Our findings reveal that a single substrate can engage an E3 ligase through multiple binding modes, affecting its degradation timing and efficiency.

Journal Keywords: cell cycle; protein ubiquitination

Subject Areas: Biology and Bio-materials

Diamond Offline Facilities: Electron Bio-Imaging Centre (eBIC)
Instruments: Krios II-Titan Krios II at Diamond , Krios III-Titan Krios III at Diamond

Added On: 10/09/2019 12:44

Documents:
s41467-019-11833-2.pdf

Discipline Tags:

Structural biology Life Sciences & Biotech

Technical Tags:

Microscopy Electron Microscopy (EM) Cryo Electron Microscopy (Cryo EM)