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Updated: Aug 13, 2026

Analysis of Cell Cycle Position in Mammalian Cells
12:19

Analysis of Cell Cycle Position in Mammalian Cells

Published on: January 21, 2012

A cell cycle-regulated inhibitor of cyclin-dependent kinases

L Hengst1, V Dulic, J M Slingerland

  • 1Department of Molecular Biology, Scripps Research Institute, La Jolla, CA 92037.

Proceedings of the National Academy of Sciences of the United States of America
|June 7, 1994
PubMed

Insights

Researchers identified p28Ick, a novel inhibitor of cyclin-dependent kinases (Cdks). This protein

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Cyclin-dependent kinases (Cdks) regulate fundamental cell cycle transitions in eukaryotes.
  • Understanding Cdk regulation is crucial for comprehending cell proliferation and development.

Purpose of the Study:

  • To identify novel regulators of the cell cycle.
  • To characterize the function of a newly discovered Cdk inhibitor, p28Ick.

Main Methods:

  • Protein identification and characterization.
  • Biochemical assays to assess kinase inhibition.
  • Cell cycle analysis.

Main Results:

  • A 28-kDa protein, p28Ick (inhibitor of cyclin-dependent kinase), was identified.
  • p28Ick directly binds to and inhibits preformed human Cdk/cyclin complexes.
  • p28 inhibitory activity peaks in the G1 phase and accumulates in G1/G0-arrested cells.

Conclusions:

  • p28Ick functions as a novel inhibitor of cyclin-dependent kinases.
  • The cell cycle inhibitory activity of p28Ick suggests its role in controlling the G1/S transition.
  • p28Ick represents a new member of the Cdk inhibitor family, alongside p21Cip1/Waf1/Cap20 and p16Ink4.

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