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A Convenient and General Expression Platform for the Production of Secreted Proteins from Human Cells
Published on: July 31, 2012
Secreted int-1 protein is associated with the cell surface
1Institute of Cancer and Developmental Biology, Syntex Research, Palo Alto, California 94304.
Molecular and Cellular Biology
|June 1, 1990
Summary
The int-1 protein is secreted and binds to the cell surface, suggesting a role in local cell-to-cell signaling during neural development and mammary tumor formation.
Area of Science:
- Molecular Biology
- Developmental Biology
- Oncology
Background:
- The int-1 proto-oncogene is involved in neural development.
- Transcriptional activation of int-1 by mouse mammary tumor virus contributes to mammary tumors.
Purpose of the Study:
- To characterize the biochemical properties of the int-1 gene product.
- To understand the function of int-1 protein in neural development and tumorigenesis.
Main Methods:
- Transfection of a neuroendocrine cell line with int-1 cDNA.
- Analysis of int-1 protein processing and secretion.
- Cell surface detection using radioiodination and antibody adsorption.
- Suramin treatment to assess protein release.
Main Results:
- Int-1 protein is efficiently processed and secreted via the constitutive secretory pathway.
- Secreted int-1 protein associates with the cell surface or extracellular matrix.
- Direct detection of int-1 protein on the cell surface was confirmed.
Conclusions:
- Int-1 protein is secreted and functions locally.
- The findings support a model of int-1 protein involved in cell-to-cell signaling.
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