A single cdk inhibitor, p27Xic1, functions beyond cell cycle regulation to promote muscle differentiation in Xenopus

Related Experiment Video

Updated: Aug 5, 2026

Adult and Embryonic Skeletal Muscle Microexplant Culture and Isolation of Skeletal Muscle Stem Cells
14:36

Adult and Embryonic Skeletal Muscle Microexplant Culture and Isolation of Skeletal Muscle Stem Cells

Published on: September 22, 2010

Ann E Vernon1, Anna Philpott

  • 1Department of Oncology, University of Cambridge, Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Addenbrooke's Hospital, Hills Road, Cambridge CB2 2XY, UK.

Development (Cambridge, England)
|November 21, 2002
PubMed

Insights

The cyclin-dependent kinase inhibitor p27(Xic1) controls muscle differentiation in Xenopus embryos. Its role in myogenesis extends beyond cell cycle inhibition, highlighting a novel function in promoting muscle development.

Area of Science:

  • Developmental Biology
  • Cell Biology
  • Molecular Biology

Background:

  • The interplay between cellular proliferation and differentiation is a fundamental process in development.
  • The precise molecular mechanisms governing cell cycle exit and differentiation remain incompletely understood.
  • Cyclin-dependent kinase inhibitors (CKIs) are key regulators of the cell cycle.

Purpose of the Study:

  • To investigate the role of the CKI p27(Xic1) in coordinating cell cycle exit and differentiation during early myogenesis.
  • To elucidate the specific functions of p27(Xic1) in muscle development in vivo.
  • To determine if p27(Xic1)'s role in myogenesis is linked to its cell cycle inhibitory function.

Main Methods:

  • Utilized Xenopus embryos as a model system for in vivo studies.
  • Examined the expression patterns of p27(Xic1) during myogenesis.
  • Investigated the effects of p27(Xic1) ablation on muscle differentiation.
  • Assessed the synergistic interaction between p27(Xic1) and the transcription factor MyoD.
  • Mapped the functional domains of p27(Xic1) responsible for promoting myogenesis.

Main Results:

  • p27(Xic1) exhibits high expression in the developing myotome.
  • Ablation of p27(Xic1) protein inhibits muscle differentiation.
  • p27(Xic1) demonstrates a synergistic effect with MyoD in promoting muscle differentiation.
  • The myogenesis-promoting activity of p27(Xic1) resides in its N-terminal domain.
  • This function is separable from its cell cycle regulatory activity.

Conclusions:

  • p27(Xic1) is a critical regulator of in vivo muscle differentiation in Xenopus.
  • p27(Xic1) influences myogenesis through mechanisms independent of its canonical cell cycle inhibition function.
  • These findings reveal a novel role for CKIs in developmental processes beyond cell cycle control.

More Related Videos

Development of Inhibitors of Protein-protein Interactions through REPLACE: Application to the Design and Development Non-ATP Competitive CDK Inhibitors10:33

Development of Inhibitors of Protein-protein Interactions through REPLACE: Application to the Design and Development Non-ATP Competitive CDK Inhibitors

Published on: October 26, 2015

Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development09:32

Light-mediated Reversible Modulation of the Mitogen-activated Protein Kinase Pathway during Cell Differentiation and Xenopus Embryonic Development

Published on: June 15, 2017

Related Concept Videos

Positive Regulator Molecules01:45

Positive Regulator Molecules

To consistently produce healthy cells, the cell cycle—the process that generates daughter cells—must be precisely regulated.
Positive Regulator Molecules02:39

Positive Regulator Molecules

Mitotic cell division results in daughter cells that exactly resemble the parent cell. However, errors in the DNA replication or distribution of genetic material may lead to genetic mutations that may be passed down to every new cell formed from the resulting abnormal cell. Propagation of such mutant cells is restricted through checkpoint mechanisms present at different stages of the cell cycle. These checkpoints involve regulator molecules that either promote or demote cell cycle events.
Inhibition of Cdk Activity02:34

Inhibition of Cdk Activity

The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
M-Cdk Drives Transition Into Mitosis02:15

M-Cdk Drives Transition Into Mitosis

Checkpoints throughout the cell cycle serve as safeguards and gatekeepers, allowing the cell cycle to progress in favorable conditions and slow or halt it in problematic ones. This regulation is known as the cell cycle control system.
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
Anaphase Promoting Complex00:50

Anaphase Promoting Complex

The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...
Inhibition of CDK Activity02:34

Inhibition of CDK Activity

The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...