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Updated: Aug 19, 2026

High-resolution Time-lapse Imaging and Automated Analysis of Microtubule Dynamics in Living Human Umbilical Vein Endothelial Cells
10:25

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Signaling, mitogenesis and the cytoskeleton: where the action is

K L Carraway1, C A Carraway

  • 1Department of Cell Biology and Anatomy, University of Miami School of Medicine, FL 33101.

Bioessays : News and Reviews in Molecular, Cellular and Developmental Biology
|February 1, 1995
PubMed

Insights

Epidermal growth factor (EGF) triggers cell growth via a signaling pathway. This pathway relies on localizing key proteins, like Ras and Raf, to the cell membrane for effective regulation.

Area of Science:

  • Cellular Biology
  • Molecular Signaling
  • Biochemistry

Background:

  • Epidermal growth factor (EGF) stimulates mitogenesis through a signaling cascade involving the EGF receptor, Ras, and MAP kinase pathway.
  • Key signaling events are proposed to occur at the plasma membrane, the location of Ras.
  • Other signaling molecules are known to function at specific cellular sites.

Purpose of the Study:

  • To propose that localization of signaling components, particularly at membrane-microfilament interfaces, is critical for cellular regulation.
  • To elucidate the role of protein localization in the EGF-mediated mitogenic pathway.

Main Methods:

  • The study proposes a model based on existing knowledge of signaling pathways.
  • It integrates observations on the localization of various signaling elements, including receptor kinases, nonreceptor tyrosine kinases, and tyrosine phosphatases.

Main Results:

  • Recruitment of Sos to the phosphorylated EGF receptor via Grb2 is a critical step at the plasma membrane.
  • Recruitment of Raf to activated Ras at the plasma membrane is another critical step.
  • Raf is proposed to associate with the cytoskeleton at the membrane during activation.

Conclusions:

  • Localization of signaling components to specific cellular sites, especially membrane-microfilament interfaces, plays a critical role in cellular regulation.
  • Spatial organization of signaling molecules is essential for signal transduction and cellular responses.

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