Correlation Engine 2.0
Clear Search sequence regions

  • Apc1 (8)
  • Cdc20 (11)
  • Cdk1 (2)
  • cell cycle (3)
  • mitosis (3)
  • subunit protein (1)
  • subunits (1)
  • ubiquitin (4)
  • xenopus (2)
  • Sizes of these terms reflect their relevance to your search.

    Cell cycle progression and genome stability are regulated by a ubiquitin ligase, the anaphase-promoting complex/cyclosome (APC/C). Cyclin-dependent kinase 1 (Cdk1) has long been implicated in APC/C activation; however, the molecular mechanisms of governing this process in vivo are largely unknown. Recently, a Cdk1-dependent phosphorylation relay within Apc3-Apc1 subunits has been shown to alleviate Apc1-mediated auto-inhibition by which a mitotic APC/C co-activator Cdc20 binds to and activates the APC/C. However, the underlying mechanism for dephosphorylation of Cdc20 and APC/C remains elusive. Here, we show that a disordered loop domain of Apc1 (Apc1-loop500 ) directly binds the B56 regulatory subunit of protein phosphatase 2A (PP2A) and stimulates Cdc20 loading to the APC/C. Using the APC/C reconstitution system in Xenopus egg extracts, we demonstrate that mutations in Apc1-loop500 that abolish B56 binding decrease Cdc20 loading and APC/C-dependent ubiquitylation. Conversely, a non-phosphorylatable mutant Cdc20 can efficiently bind the APC/C even when PP2A-B56 binding is impeded. Furthermore, PP2A-B56 preferentially dephosphorylates Cdc20 over the Apc1 inhibitory domain. These results indicate that Apc1-loop500 plays a role in dephosphorylating Cdc20, promoting APC/C-Cdc20 complex formation in mitosis. © 2019 The Authors. Published under the terms of the CC BY 4.0 license.


    Kazuyuki Fujimitsu, Hiroyuki Yamano. PP2A-B56 binds to Apc1 and promotes Cdc20 association with the APC/C ubiquitin ligase in mitosis. EMBO reports. 2020 Jan 07;21(1):e48503

    Expand section icon Mesh Tags

    Expand section icon Substances

    PMID: 31825153

    View Full Text