Cytoskeleton Structure



The cytoskeleton is a complex network of protein filaments that defines cell shape; provides the cell with structural support, intracellular transport, and motility; and facilitates cell division and response to the environment. The three families of filaments that make up the eukaryotic cytoskeleton are actin filaments, microtubules, and intermediate filaments. Actin filaments deal predominantly with cell shape and cell adhesion, but they also interact with the motor protein myosin to move materials within cells. Microtubules are associated with movement via kinesin and dynein. Actin filaments and microtubules are dynamic structures, while intermediate filaments are more stable. The several types of intermediate filaments each play a specific structural role in strengthening the cell.

At A Glance

  • The cytoskeleton gives animal cells structure, strength, and the ability to change shape and move.
  • Actin is the protein that makes up the actin filament, which plays a central role in cell shape, cell movement, and muscle contraction.
  • Microtubules are filaments involved in cellular mitosis and movement, whereas intermediate filaments primarily serve as structural proteins in eukaryotic cells.
  • Intermediate filaments are strong, fibrous proteins that provide structural support in eukaryotic cells.
  • Microtubules are hollow tubules that help organize and move materials and organelles inside the cell, including the genetic material during cell division.
  • The dynamic instability of microtubules enables a cell to rapidly switch between either building microtubules or disassembling microtubules, depending on the needs of each area of the cell.
  • Kinesins and dyneins are two types of motor proteins that help to move cellular components along microtubules within the cell.