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Updated: Aug 8, 2026
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Analysis of Protein-protein Interactions and Co-localization Between Components of Gap, Tight, and Adherens Junctions in Murine Mammary Glands
Published on: May 30, 2017
Maspin is physically associated with [beta]1 integrin regulating cell adhesion in mammary epithelial cells
Nathalie Cella1, Alejandro Contreras, Khatri Latha
1Baylor College of Medicine, Department of Molecular and Cellular Biology, ALKEK Bldg., Rm. N630, One Baylor Plaza, Houston, Texas 77030, USA.
Summary
Maspin, a tumor-suppressor protein, enhances mammary cell adhesion to the extracellular matrix. This protein functions within the cell's adhesion structures, mediated by beta1 integrin.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Maspin is a tumor-suppressor serpin (serine protease inhibitor) known to inhibit cell invasion and migration.
- Understanding maspin's role in cell adhesion is crucial for its function in non-transformed mammary epithelial cells.
Purpose of the Study:
- To analyze maspin's function in cell adhesion in nontransformed mammary epithelial cells.
- To investigate the underlying molecular mechanisms of maspin's effect on cell adhesion.
Main Methods:
- Utilized recombinant maspin to assess its impact on MCF-10A cell adhesion to endogenous matrix.
- Employed antimaspin antibody and RNA interference for maspin knockdown studies.
- Conducted mutation analyses to identify the functional region of maspin involved in adhesion.
- Investigated maspin's association with cellular cytoskeleton components.
Main Results:
- Recombinant maspin addition significantly increased MCF-10A cell adhesion.
- Antimaspin antibody and maspin knockdown led to decreased cell adhesion.
- A specific 86-amino acid region (aa 139-225) was identified as critical for maspin's adhesion-promoting effect.
- Maspin was found to associate with detergent-insoluble cortical cytoskeleton elements.
Conclusions:
- Maspin plays a role in the early stages of cell adhesion.
- Maspin is integrated into the supramolecular structure of the adhesion plaque.
- Maspin modulates cell adhesion through a beta1 integrin-dependent mechanism.
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