Involvement of Rab13 and JRAB/MICAL-L2 in epithelial cell scattering
I Kanda1, N Nishimura, H Nakatsuji
1Department of Biochemistry, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan.
Oncogene
|September 25, 2007
Summary
Rab13 and its effector JRAB/MICAL-L2 are crucial for epithelial cell scattering, a key step in carcinoma invasion. Their activation and localization regulate cell motility and adhesion during this process.
Area of Science:
- Cell Biology
- Cancer Research
- Molecular Biology
Background:
- Epithelial cell scattering is a critical early step in carcinoma invasion and metastasis.
- The molecular mechanisms governing cell-cell adhesion and motility during scattering are not fully understood.
- Tight junctions (TJs) are vital for cell adhesion and undergo dynamic remodeling.
Purpose of the Study:
- To investigate the role of Rab13 and its effector JRAB/MICAL-L2 in epithelial cell scattering.
- To elucidate the molecular mechanisms by which Rab13 and JRAB/MICAL-L2 influence cell motility and adhesion.
Main Methods:
- Utilized Madin-Darby canine kidney (MDCK) cells treated with 12-O-tetradecanoylphorbol-13-acetate (TPA) to induce cell scattering.
- Employed knockdown techniques for Rab13 and JRAB/MICAL-L2, followed by re-expression studies.
- Analyzed the localization and activation status of Rab13 and JRAB/MICAL-L2 during TPA-induced scattering using immunofluorescence and biochemical assays.
Main Results:
- Knockdown of Rab13 suppressed TPA-induced MDCK cell scattering, which was restored upon re-expression.
- Rab13 and JRAB/MICAL-L2 were found to colocalize with F-actin at cell-cell contacts and lamellipodia during scattering.
- JRAB/MICAL-L2 knockdown also inhibited scattering, with rescue observed upon re-expression.
Conclusions:
- Rab13 and JRAB/MICAL-L2 play significant roles in regulating epithelial cell scattering.
- These proteins are involved in the dynamic remodeling of cell-cell junctions and the regulation of cell motility during invasion.
- Findings provide insights into the molecular basis of carcinoma metastasis.
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