Clathrin is spindle-associated but not essential for mitosis
Joana Borlido1, Greg Veltri, Antony P Jackson
1Uro-Oncology Research Group, CRUK Cambridge Research Institute, Li Ka Shing Cancer Research Centre, Cambridge, United Kingdom.
Plos One
|September 5, 2008
Summary
Clathrin
Area of Science:
- Cell Biology
- Molecular Biology
Background:
- Clathrin is a protein crucial for vesicle coat assembly.
- Clathrin distribution changes during the cell cycle and associates with the mitotic spindle.
Purpose of the Study:
- To investigate if clathrin's recruitment to the mitotic spindle indicates a critical role in mitosis.
- To explore the significance of clathrin heavy chain expression for cell cycle progression.
Main Methods:
- Utilized a chicken pre-B lymphoma cell line (DKO-R) with a tetracycline-regulatable promoter for clathrin heavy chain expression.
- Confirmed clathrin colocalization with tubulin at mitotic spindles using confocal microscopy.
- Assessed cell cycle distribution, ploidy, and recovery kinetics after nocodazole arrest using propidium iodide flow cytometry.
Main Results:
- Clathrin knockout significantly inhibited receptor-mediated and fluid-phase endocytosis.
- No statistical difference in cell cycle distribution was observed between knockout and wild-type cells.
- Repressing clathrin heavy chain expression did not alter ploidy or recovery kinetics post-nocodazole arrest.
Conclusions:
- Clathrin's association with the mitotic spindle and its role in endocytosis are evolutionarily conserved.
- Clathrin's contribution to mitosis is context-dependent and less robust than its role in endocytosis.
- Further research is needed to understand the molecular mechanisms of clathrin recruitment and function at the spindle.
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