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Static Adhesion Assay for the Study of Integrin Activation in T Lymphocytes
Published on: June 13, 2014
Calreticulin and focal-contact-dependent adhesion
Maria Villagomez1, Eva Szabo, Alexey Podcheko
1Department of Laboratory Medicine and Pathobiology, University of Toronto, 1 King's College Circle, Medical Sciences Building, Toronto, ON M5S 1A8, Canada.
Biochemistry and Cell Biology = Biochimie Et Biologie Cellulaire
|September 22, 2009
Summary
Calreticulin, an ER-resident protein, regulates cell adhesion through ER-to-nucleus and ER-to-cell surface signaling pathways. It impacts focal contact formation and turnover, influencing cell-substratum adhesion.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Cell adhesion is crucial for multicellular organisms.
- Calcium-regulated pathways and Ca2+-binding proteins mediate cell adhesion.
- Calreticulin is an ER-resident protein involved in Ca2+ regulation.
Purpose of the Study:
- To review the role of calreticulin in cell adhesion.
- To explore calreticulin's involvement in focal contact dynamics.
- To propose signaling mechanisms by which calreticulin regulates cell-substratum adhesion.
Main Methods:
- Literature review of calreticulin's function in cell adhesion.
- Analysis of calreticulin's impact on gene expression (vinculin, fibronectin).
- Investigation of calreticulin's effect on protein tyrosine phosphorylation.
Main Results:
- ER-resident calreticulin influences focal-contact-dependent adhesion.
- Calreticulin expression levels affect tyrosine phosphorylation, impacting adhesion.
- Calreticulin outside the ER may be involved in contact disassembly.
Conclusions:
- Calreticulin plays a dual role in cell adhesion, both initiating/stabilizing and potentially disassembling focal contacts.
- Calreticulin regulates cell-substratum adhesion via "ER-to-nucleus" and "ER-to-cell surface" signaling.
- Posttranslational modifications are likely involved in calreticulin-mediated adhesion signaling.
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