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Intracellular expression of the monoclonal anti-ras antibody Y13-259 blocks the transforming activity of ras

X Montano1, A Jimenez

  • 1National Cancer Institute, Frederick Cancer Research Facility, Maryland 21701, USA.

Cell Growth & Differentiation : the Molecular Biology Journal of the American Association for Cancer Research
|May 1, 1995
PubMed

Insights

Researchers developed a method for intracellular antibody production to study ras gene function. This approach successfully reverted ras-transformed cells to a normal phenotype, offering a new tool for biological analysis.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Oncology

Background:

  • Investigating gene function often involves understanding protein regulation.
  • Intracellular production of neutralizing antibodies offers a novel approach to study gene regulation.
  • Ras proteins are key regulators of cell growth and transformation.

Purpose of the Study:

  • To develop a system for intracellular expression of anti-ras antibodies.
  • To investigate the role of ras in cellular transformation.
  • To demonstrate the utility of intracellular antibodies for analyzing protein function.

Main Methods:

  • Isolated genes for heavy and light chains of anti-ras antibody (Mab Y13-259).
  • Transfected NIH3T3 cells with expression vectors for antibody chains, removing leader sequences for cytoplasmic entry.
  • Utilized inducible promoters (MSV LTR, MMTV LTR) for controlled antibody expression in the presence of dexamethasone.

Main Results:

  • Functional anti-ras antibody was produced intracellularly without requiring glycosylation.
  • Expression of intracellular anti-ras antibody in ras-transformed cells led to phenotypic reversion.
  • Demonstrated that intracellular antibody expression can modulate ras function and cellular phenotype.

Conclusions:

  • Intracellular antibody expression is a viable method for studying gene function and protein regulation.
  • This technique provides a powerful tool for analyzing the biological roles of specific proteins like ras.
  • The study highlights a novel strategy for targeting oncogenic proteins and potentially developing new cancer therapies.

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