If every organelle were eliminated from a cell, the plasma membrane and cytoplasm would not be the only components left. There would still be organic molecules and ions present in the cytoplasm along with a network of protein fibers that assist in maintaining the shape of the cell. These fibers acquire certain organelles in particular positions and allow vesicles and cytoplasm to move in the cell and let unicellular organisms to move freely. The network of protein fibers is called the cytoskeleton. There exist three kinds of fibers in the cytoskeleton namely: intermediate filaments, microfilaments, and microtubules among which microfilaments are the most narrow fiber.
What are Microfilaments?
Microfilaments, also called actin filaments, as they consist of two intertwined strands of a globular protein known as actin. They are the polymers of the protein actin and are smallest filaments of the cytoskeleton. They have a vital role in cell movements, cell division, and muscle contraction.
Structure and Functions of Microfilaments
Microfilaments are the leanest filaments of the cytoskeleton present in the cytoplasm of eukaryotic cells with a diameter of about 5 to 8 nanometers. The polymers of these filaments are flexible but very strong and resist buckling and crushing while offering support to the cell.
Microfilaments are versatile components and play a major role in cytokinesis and shape of a cell. The flexible arrangement of filaments framework enables it to help in cell movement.
The filaments play a vital role in contracting molecular motors driven by the actomyosin. In such processes, the lean filaments become expanding platforms for the pulling action of myosins. It occurs mainly during pseudopod development and contraction.
Microfilaments provide shape and rigidity to the cell. They can disassemble and re uniform rapidly hence enable a cell to modify its shape and move. The white blood cells utilize this ability to a good extent and could reach the site of infection and submerge the pathogens.
Stay tuned with BYJU’S to learn more about microfilaments and their functions in the eukaryotic cells.