Figure 1.

Interaction between growth arrest specific 6 (Gas6) and TAM (Tyro3, Axl and Mer) receptors. The sex hormone-binding globulin (SHBG) domain of Gas6, made of two globular laminin-G like repeats, interacts with the immunoglobulin-like domain of the TAM receptors. The extracellular portion is completed by two fibronectin 3 repeats, while the tyrosine kinase activity is played by the intracellular region of the receptor. ADAM10 and ADAM17 are two metalloproteinases responsible of TAM receptors cleavage. Their proteolytic domain cleaves TAM receptors in close proximity to the transmembrane domain, leading to the formation of soluble TAM (sTAM). sTAM receptors inhibit Gas6 activity by acting both as decoy receptors and reducing the number of ligand sites on the cell membrane (see text for further explanations and references). Ig, immunoglobulin; EGF, epidermal growth factor.