After completing this topic, medical students should be able to identify the major cytoskeletal elements, their structural components, and their clinical relevance in cellular processes and diseases (e.g., movement disorders, intermediate filament pathology).
Overview
The cytoskeleton is a dynamic network of protein fibers within the cytoplasm that provides mechanical support, facilitates cell movement and intracellular transport, and participates in cell division.
Types of Cytoskeletal Filaments
| Type of Filament | Predominant Function | Examples / Key Proteins | Clinical Correlation |
|---|---|---|---|
| Microfilaments (Actin filaments) | Muscle contraction, cytokinesis, phagocytosis, and cell motility |
|
Defect in actin polymerization
|
| Intermediate filaments | Maintain cell structure and tensile strength |
|
Tumor markers:
|
| Microtubules | Intracellular transport, cell division, and motility |
|
Drugs acting on microtubules:
Defects: Kartagener syndrome (dynein arm defect) |
Key Points
- The cytoskeleton is essential for cell integrity, intracellular trafficking, and motility.
- Intermediate filaments are often used as diagnostic markers in pathology.
- Microtubule inhibitors are important anticancer and antiparasitic agents.
- Actin filaments drive processes like phagocytosis and cytokinesis.
Clinical Integration
- Kartagener syndrome (defective ciliary dynein → infertility, sinusitis)
- Mallory bodies in hepatocytes (cytokeratin accumulation)
- Neurofibrillary tangles in Alzheimer’s disease (neurofilament and tau abnormalities)
