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Updated: Aug 8, 2026

Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells
10:27

Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells

Published on: March 9, 2012

Spatiotemporal organization of Ras signaling: rasosomes and the galectin switch

Uri Ashery1, Ofer Yizhar, Barak Rotblat

  • 1Department of Neurobiochemistry, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.

Cellular and Molecular Neurobiology
|May 13, 2006
PubMed

Insights

Ras protein interactions with cellular compartments are key to oncogenesis. Farnesyl groups and palmitoylation dictate Ras localization and signaling, influencing cancer development.

Area of Science:

  • Cellular Biology
  • Molecular Biology
  • Oncogenesis

Background:

  • Ras signaling is crucial for cell growth and is implicated in oncogenesis.
  • Ras protein interactions with cellular compartments are dynamic and influence signaling pathways.
  • Specific elements within the Ras carboxy-terminal domain, including farnesyl and palmitoyl groups, regulate these interactions.

Purpose of the Study:

  • To elucidate how Ras protein interactions with distinct cellular compartments are regulated.
  • To understand the role of specific Ras domains in localization and signaling.
  • To investigate the impact of these interactions on Ras-driven oncogenesis.

Main Methods:

  • Analysis of Ras protein carboxy-terminal domain elements (farnesyl, hypervariable region-linker, palmitoyl groups).
  • Investigation of interactions with plasma membrane microdomains and intracellular compartments.
  • Study of galectin-1, galectin-3, and cGMP phosphodiesterase delta binding.
  • Examination of H-Ras, N-Ras, and K-Ras signaling pathways.

Main Results:

  • The farnesyl group mediates interactions with galectins and phosphodiesterase delta, affecting Ras signal duration and effector choice.
  • Galectin-1 and galectin-3 differentially regulate H-Ras and K-Ras signaling.
  • Hypervariable region-linker and palmitoylation control Ras localization to plasma membrane, Golgi, and 'rasosomes'.
  • Dynamic compartmentalization spatially organizes Ras signaling and enhances selectivity.

Conclusions:

  • Ras protein compartmentalization is a critical regulatory mechanism in Ras signaling.
  • Specific lipid modifications and protein interactions dictate Ras localization and downstream effects.
  • Understanding these dynamics offers insights into Ras-driven oncogenesis and potential therapeutic targets.

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