The integrin heterodimer can exist

The integrin heterodimer can exist in either an active state that engages ECM, actin filaments, and other associated proteins, or in an inactive state. This switch of state allows cells to exert or disengage internal and external mechanical interaction. The switch of state is facilitated by coupling to a cells signaling proteins. The cell—matrix junction is associated with signaling kinases or other signaling system proteins. The signal transmission occurs from both sides of the cellular membrane, from intracellular to extracellular environment and vice versa. The binding of integrin to ECM proteins can activate integrin to allow for binding by actin filaments. Conversely; internal signaling activation of integrin can also initiate the connection of actin filaments and ECM through integrin.