Identification of Xenopus cyclin-dependent kinase inhibitors, p16Xic2 and p17Xic3

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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

Maki Daniels1, Vishal Dhokia, Laurent Richard-Parpaillon

  • 1Department of Oncology, The Hutchison/MRC Research Centre, University of Cambridge, Hills Road, Cambridge, CB2 2XZ, UK.

Gene
|November 6, 2004
PubMed

Insights

Two novel cyclin-dependent kinase (cdk) inhibitors, p16Xic2 and p17Xic3, were identified in Xenopus. These inhibitors regulate cell cycle progression and influence cell fate determination during development.

Area of Science:

  • Developmental Biology
  • Cell Cycle Regulation
  • Molecular Biology

Background:

  • The Cip/Kip family of cyclin-dependent kinase (cdk) inhibitors is crucial for development, regulating cell fate and differentiation.
  • These inhibitors also block cell cycle progression.

Purpose of the Study:

  • To identify and characterize novel members of the Kip/Cip cdk inhibitor family in Xenopus laevis.
  • To investigate the roles of these novel inhibitors in cell cycle control and cell fate determination.

Main Methods:

  • Sequence analysis to identify novel cdk inhibitors.
  • Overexpression studies to assess effects on cell cycle progression and cdk2 activity.
  • Expression pattern analysis during development.
  • Retinal cell fate determination assays.

Main Results:

  • Two novel Xenopus Kip/Cip inhibitors, p16Xic2 and p17Xic3, were identified as orthologues of mammalian p21Cip1 and p27Kip1.
  • Overexpression of p16Xic2 and p17Xic3 caused cell cycle arrest by inhibiting cdk2 activity.
  • Expression of these inhibitors is developmentally regulated and tissue-specific.
  • Both inhibitors influenced cell fate determination in a retinal assay.

Conclusions:

  • p16Xic2 and p17Xic3 are Xenopus cdk inhibitors involved in regulating cell proliferation and differentiation.
  • These inhibitors likely play tissue-specific roles in cell fate determination during development.
  • Their function parallels that of mammalian p27Xic1 in coordinating proliferation and differentiation.

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