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Updated: Aug 11, 2026

Spatial and Temporal Analysis of Active ERK in the C. elegans Germline
08:40

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Published on: November 29, 2016

Signal transduction: implications for Ras-dependent ERK signaling

Stéphane Ory1, Deborah K Morrison

  • 1Laboratory of Protein Dynamics and Signaling, NCI-Frederick, Frederick, Maryland 21702, USA.

Current Biology : CB
|April 6, 2004
PubMed

Insights

A newly identified E3 ubiquitin ligase, Impedes Mitogenic signal Propagation (IMP), binds to Ras proteins. IMP regulates MAP kinase signaling by controlling the scaffolding activity of KSR, impacting cellular communication.

Area of Science:

  • Cellular signaling pathways
  • Molecular biology
  • Protein ubiquitination

Background:

  • Ras proteins are key regulators of diverse cellular signals.
  • Mitogenic signal propagation involves complex downstream effector interactions.
  • Understanding protein regulation is crucial for deciphering cellular communication.

Purpose of the Study:

  • To identify novel regulators of Ras-mediated signaling.
  • To characterize the function of the Impedes Mitogenic signal Propagation (IMP) protein.
  • To elucidate the mechanism by which IMP modulates MAP kinase signaling.

Main Methods:

  • Protein-protein interaction assays to confirm binding of IMP to Ras.
  • Biochemical assays to determine E3 ubiquitin ligase activity of IMP.
  • In vitro and in vivo experiments to assess the impact of IMP on KSR scaffolding and MAP kinase pathway activation.

Main Results:

  • The protein Impedes Mitogenic signal Propagation (IMP) was identified as an E3 ubiquitin ligase.
  • IMP directly binds to Ras proteins.
  • IMP modulates MAP kinase signaling by regulating the scaffolding activity of KSR.

Conclusions:

  • IMP is a novel E3 ubiquitin ligase that acts as a critical regulator in the Ras signaling pathway.
  • IMP's interaction with Ras and modulation of KSR scaffolding provide new insights into the control of MAP kinase signaling.
  • Targeting IMP may offer therapeutic strategies for diseases involving aberrant Ras signaling.

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