Related Experiment Video

Updated: Mar 8, 2026

Nitrogen Cavitation and Differential Centrifugation Allows for Monitoring the Distribution of Peripheral Membrane Proteins in Cultured Cells
08:24

Nitrogen Cavitation and Differential Centrifugation Allows for Monitoring the Distribution of Peripheral Membrane Proteins in Cultured Cells

Published on: August 18, 2017

17.2K

Where no Ras has gone before: VPS35 steers N-Ras through the cytosol

Mo Zhou1, Mark R Philips1

  • 1a Perlmutter Cancer Center, New York University School of Medicine , New York , NY , USA.

Small Gtpases
|January 28, 2017
PubMed

Insights

This study reveals N-Ras is primarily cytosolic, unlike other Ras proteins. VPS35 regulates N-Ras trafficking and signaling, impacting cancer cell proliferation and MAPK pathways.

Area of Science:

  • Cellular biology
  • Molecular biology
  • Cancer research

Background:

  • Ras proteins are key regulators of cell signaling, proliferation, differentiation, and survival.
  • All Ras isoforms were traditionally considered membrane-bound, a prerequisite for their function.
  • Dysregulation of Ras signaling is implicated in various cancers.

Purpose of the Study:

  • To investigate the subcellular localization and regulatory mechanisms of N-Ras.
  • To identify novel proteins interacting with N-Ras in the cytosol.
  • To elucidate the role of these interactions in N-Ras signaling and cancer cell behavior.

Main Methods:

  • Subcellular fractionation and chromatography to analyze N-Ras localization.
  • Co-immunoprecipitation to identify interacting proteins.
  • VPS35 gene silencing (e.g., using siRNA) to assess its impact on N-Ras.
  • Analysis of Ras GTP-loading, MAPK signaling, and cell proliferation assays.

Main Results:

  • N-Ras was found to be predominantly cytosolic, even after prenylation, distinguishing it from other Ras isoforms.
  • Prenylated N-Ras interacts with VPS35, a component of the retromer complex, in the cytosol.
  • VPS35 silencing led to N-Ras mislocalization to vesicular structures, decreased Ras GTP-loading, and inhibited proliferation and MAPK signaling in an N-Ras-driven cancer cell line.

Conclusions:

  • N-Ras exhibits unique cytosolic localization and prenyl-dependent interactions.
  • VPS35 acts as a novel regulator of N-Ras trafficking and signaling.
  • Targeting the N-Ras-VPS35 interaction may offer new therapeutic strategies for N-Ras-driven cancers.
Keywords:
N-RasRasVPS35cytosolic proteinoncogeneprenylationtrafficking

More Related Videos

Fully Processed Recombinant KRAS4b: Isolating and Characterizing the Farnesylated and Methylated Protein07:08

Fully Processed Recombinant KRAS4b: Isolating and Characterizing the Farnesylated and Methylated Protein

Published on: January 16, 2020

6.2K
Detection of Small GTPase Prenylation and GTP Binding Using Membrane Fractionation and GTPase-linked Immunosorbent Assay13:51

Detection of Small GTPase Prenylation and GTP Binding Using Membrane Fractionation and GTPase-linked Immunosorbent Assay

Published on: November 11, 2018

10.4K

Related Concept Videos

The Ras Gene02:38

The Ras Gene

The Ras-gene-encoded proteins are regulators of signaling pathways controlling cell proliferation, differentiation, or cell survival. The Ras-gene family in humans constitutes three primary members—the HRas, NRas, and KRas. These genes code for four functionally distinct yet closely related proteins—the HRas, NRas, KRas4A, and KRas4B. The involvement of mutant Ras genes in human cancer was first discovered in 1982 and is among the most common causes of human tumorigenesis.
Ras is a...
7.4K
Small GTPases - Ras and Rho01:24

Small GTPases - Ras and Rho

Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
5.6K
Rab Proteins01:14

Rab Proteins

Rab proteins constitute the largest family of monomeric GTPases, of which 70 members are present in humans. Rab proteins and their effectors regulate consecutive stages of vesicle transport such as vesicle transport, docking, and fusion to the correct recipient membrane.
Rab proteins switch between a cytosolic, GDP-bound inactive state and a membrane-anchored, GTP-bound active state. By themselves, Rabs show slow rates of GDP/GTP exchange and GTP hydrolysis. Thus, Rab proteins are considered...
5.3K
GPI Anchoring of Proteins in the ER Membrane01:29

GPI Anchoring of Proteins in the ER Membrane

GPI-anchoring is a post-translational, reversible protein modification that is ubiquitous in eukaryotes. Such proteins are primarily present on the exoplasmic leaflet of the plasma membrane.
GPI-anchor structure
A sequence of 11 enzymatic reactions results in the synthesis of the complete GPI anchor consisting of a hydrophobic and a hydrophilic portion. The hydrophobic portion comprises phosphatidylinositol, while the hydrophilic part comprises polar groups like phosphoethanolamine,...
5.7K
Directing Proteins to the Rough Endoplasmic Reticulum01:34

Directing Proteins to the Rough Endoplasmic Reticulum

The organelle-specific signaling sequences direct proteins synthesized in the cytosol to their final destination like ER, mitochondria, peroxisomes, etc. Some of the proteins directed to ER are then trafficked via vesicles to other organelles within the cell or the extracellular environment through the Golgi complex. For example, the rough ER synthesizes soluble proteins for transportation to the lysosomes or secretion out of the cell. It can also synthesize transmembrane proteins that can...
18.1K
Cell Polarization by Rho Proteins01:21

Cell Polarization by Rho Proteins

Cell polarity is the asymmetric distribution of cellular and membrane components, making one side of the cell different from the other. This polarity is essential to many processes such as embryogenesis, axon migration, glucose transport across epithelial cells, and directional cell migration. A migrating cell responds to intracellular or extracellular signals via molecular cascades that reorganize the actin cytoskeleton to establish this polarity. In these cells, the Rho family proteins Cdc42,...
3.9K