Integrins are heterodimers comprised of alpha and beta subunits, that are noncovalently associated transmembrane glycoprotein receptors. Integrins not only transmit signals to cells in response to the extracellular environment (outside-in signaling), but also sense intracellular cues to alter their interaction with extracellular environment (inside-out signaling). ITGB4, also known as CD104, is a 1,822 amino acid single-pass type I membrane protein belonging to the Integrin chain family. Integrin β4 is an important component in several growth factor induced signaling pathways that are involved in tumorigenesis and invasive cell growth.
