AAT Bioquest

What are the functions of actin filaments?

Posted November 21, 2022


Actin filaments, also known as microfilaments, are the smallest protein fiber in the cytoskeleton, measuring about 7 nm in diameter. They are especially abundant just below the plasma membrane, where they form an extensive network that performs several crucial functions including: 

  • Forming a dynamic cytoskeleton that provides cells with structural support 
  • Determining cell shape
  • Enabling and supporting cell motility, such as through the formation and function of Lamellipodia or Filopodia
  • Linking the cell’s interior to its surroundings 
  • Facilitating movement of the cell surface, allowing cells to migrate, engulf particles and divide 
  • Supporting muscle contraction in muscle cells 

In addition, motor proteins use actin cables as pathways to transport intracellular organelles to the daughter cells during mitosis.

Additional resources

Actin Structure and Function

Cell Structures and Organelles

Cell Navigator® F-Actin Labeling Kit *Blue Fluorescence*