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09:38
Analyzing the Function of Small GTPases by Microinjection of Plasmids into Polarized Epithelial Cells
Published on: May 31, 2011
Coordinated protein sorting, targeting and distribution in polarized cells.
1Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, USA. mellman.ira@gene.com
Nature Reviews. Molecular Cell Biology
|October 24, 2008
Summary
Cellular functions rely on coordinated protein trafficking. Three key systems ensure proteins reach correct plasma membrane domains, crucial for tissue health and often impaired in diseases.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Polarized cells exhibit asymmetric distribution of functions.
- Intracellular protein trafficking is essential for cell polarity.
- Dysregulation of protein distribution is linked to various diseases.
Purpose of the Study:
- To elucidate the coordinated mechanisms governing polarized protein distribution in cells.
- To understand how protein trafficking, signaling, and adhesion integrate for cell polarity.
- To identify the role of these integrated mechanisms in tissue function and disease.
Main Methods:
- Analysis of intrinsic protein-sorting signals and cellular decoding machineries.
- Investigation of intracellular signaling complexes and their role in domain definition.
- Examination of cell-cell and cell-substrate adhesion proteins in orienting signaling complexes and membrane traffic.
Main Results:
- Identified three interacting machineries regulating protein trafficking to specific plasma membrane domains.
- Demonstrated that signaling complexes define delivery domains, while adhesion proteins orient these complexes.
- Highlighted the integration of these systems into a dynamic network essential for cellular organization.
Conclusions:
- The coordinated interplay of protein sorting, signaling, and adhesion is fundamental for establishing and maintaining cell polarity.
- This complex network is critical for normal tissue function.
- Defects in this integrated system contribute to the pathogenesis of various diseases.
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