WARTS tumor suppressor is phosphorylated by Cdc2/cyclin B at spindle poles during mitosis

Related Experiment Video

Updated: Sep 29, 2026

Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay
12:26

Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay

Published on: May 3, 2018

Tetsuro Morisaki1, Toru Hirota, Shin-ichi Iida

  • 1Department of Tumor Genetics and Biology, Kumamoto University School of Medicine, 2-2-1 Honjo, Kumamoto 860-0811, Japan.

FEBS Letters
|October 10, 2002
PubMed

Insights

Cdc2/cyclin B phosphorylates WARTS during mitosis, regulating its function in the mitotic apparatus. This finding links mitotic events to Cdc2/cyclin B activation and WARTS function.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Understanding Cdc2/cyclin B substrates is key to linking mitotic events with its activation.
  • WARTS (warts tumor suppressor homolog) is a serine/threonine kinase and part of the mitotic apparatus.

Purpose of the Study:

  • To identify physiological substrates for Cdc2/cyclin B.
  • To investigate the role of WARTS in mitosis and its regulation by Cdc2/cyclin B.

Main Methods:

  • Complex formation analysis between Cdc2/cyclin B and WARTS.
  • Phosphorylation site identification (Ser613).
  • Immunocytochemical analysis of S613-phosphorylated WARTS localization during mitosis.

Main Results:

  • Cdc2/cyclin B forms a complex with WARTS in the centrosome.
  • Cdc2/cyclin B phosphorylates WARTS at the Ser613 site during mitosis.
  • S613-phosphorylated WARTS localizes to spindle poles from prometaphase to telophase.

Conclusions:

  • Cdc2/cyclin B directly regulates WARTS function during mitosis.
  • Phosphorylation of WARTS at Ser613 by Cdc2/cyclin B is critical for its mitotic apparatus functions.

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