Related Experiment Video

Updated: Aug 9, 2026

Characterize Disease-related Mutants of RAF Family Kinases by Using a Set of Practical and Feasible Methods
07:49

Characterize Disease-related Mutants of RAF Family Kinases by Using a Set of Practical and Feasible Methods

Published on: July 17, 2019

p21ras: an oncoprotein functioning in growth factor-induced signal transduction

J L Bos1

  • 1Laboratory for Physiological Chemistry, Universiteit Utrecht, The Netherlands.

European Journal of Cancer (Oxford, England : 1990)
|July 1, 1995
PubMed

Insights

Mutated p21ras (RAS oncogene family) proteins are constitutively active in 50% of colorectal tumors, driving aberrant cell signaling. Understanding these pathways is crucial for cancer research.

Area of Science:

  • Molecular Biology
  • Cellular Signaling
  • Oncology

Background:

  • p21ras (RAS oncogene family) is a GTPase acting as a molecular switch in signal transduction.
  • Growth factors activate p21ras, which is frequently mutated in colorectal tumors, leading to constitutive activity.

Purpose of the Study:

  • To elucidate the signaling pathways involving p21ras.
  • To understand the role of mutated p21ras in colorectal tumorigenesis.

Main Methods:

  • Analysis of intracellular signal transduction pathways.
  • Investigating the interaction of p21ras with downstream effectors like raf1.
  • Studying kinase cascade activation.

Main Results:

  • Ligand binding to growth factor receptors activates guanine nucleotide exchange factors, leading to GTP-bound p21ras.
  • GTP-bound p21ras activates raf1, initiating a kinase cascade.
  • This cascade mediates cellular responses and is part of a complex signaling network.

Conclusions:

  • Mutated p21ras plays a significant role in colorectal cancer by maintaining constitutive signaling.
  • The p21ras-raf1 pathway is a key component of integrated cellular signaling networks.
  • Further research into these pathways may reveal therapeutic targets for colorectal cancer.

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