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Published on: April 3, 2014
A dynamic podosome-like structure of epithelial cells
Laura Spinardi1, Jens Rietdorf, Lucio Nitsch
1DIBIT, Department of Biological and Technological Research, San Raffaele Scientific Institute and University Vita-Salute San Raffaele, 20132 Milan, Italy. spinardi.laura@hsr.it
Experimental Cell Research
|April 20, 2004
Summary
Hemidesmosomes in epithelial cells assemble around actin cores, similar to podosomes found in other cell types. This process is crucial for cell-matrix adhesion and is regulated by specific proteins and actin polymerization.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Focal contacts and hemidesmosomes are key cell-matrix adhesion structures.
- Focal contacts connect to microfilaments, while hemidesmosomes connect to intermediate filaments.
Purpose of the Study:
- To analyze hemidesmosome assembly in 804G carcinoma cells.
- To investigate the role of actin filaments and associated proteins in hemidesmosome formation.
Main Methods:
- Analysis of hemidesmosome assembly in 804G carcinoma cells.
- Utilized video microscopy to observe dynamic processes.
- Investigated protein localization and dependencies using biochemical and cellular techniques.
Main Results:
- Hemidesmosomes are organized around actin filament cores, resembling podosomes.
- These podosome-like structures contain Arp3 (Arp2/3 complex), cortactin, and other key proteins.
- Integrin alpha3beta1 localizes around F-actin cores, and beta4 integrin is recruited before hemidesmosome assembly.
Conclusions:
- Podosome-like structures are involved in epithelial cell-matrix adhesion.
- Hemidesmosome assembly depends on actin polymerization, src-family kinases, and Grb2.
- During migration, actin cores and hemidesmosomes disassemble, with beta4 integrin co-localizing with dynamic actin at leading edges.
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