CDC20

In Toxoplasma gondii, TgCdc20 was identified as a candidate phosphorylation substrate of the TgCrk4-TgCyc4 CDK complex in a global phosphoproteome screen, placing it downstream of cell cycle kinase signaling (PMID:38600241). Beyond this single phosphoproteomic association, no direct mechanistic detail of TgCdc20's own function, partners, or role has been characterized in the available corpus.

1. 2024 Low

   To map the substrate landscape of the cell cycle kinase TgCrk4, a phosphoproteome screen tested which proteins are phosphorylated in a TgCrk4-dependent manner, and identified TgCdc20 as a candidate substrate — the first mechanistic link placing TgCdc20 under CDK-complex regulation.

   Evidence Global mass spectrometry-based phosphoproteome analysis of TgCrk4-TgCyc4 substrates in Toxoplasma gondii

   PMID:38600241

   Open questions at the time

   • Single phosphoproteomics screen without in vitro kinase assay or phosphosite mutagenesis to validate TgCdc20 as a bona fide direct substrate
   • No functional characterization of TgCdc20's own activity, interactors, or cell cycle role
   • Whether phosphorylation regulates TgCdc20 activity or localization is untested

• The molecular function of TgCdc20, its downstream effectors, and the functional consequence of its phosphorylation by TgCrk4-TgCyc4 remain unestablished.
• No experimental determination of TgCdc20's own biochemical activity
• No identified binding partners or substrates of TgCdc20
• No genetic or phenotypic evidence for its role in cell cycle progression