Dtk, also called Tyro3, belongs to the TAM receptor family of receptor protein tyrosine kinases (RPTKs) composed of three receptors Tyro3, Axl, and Mer. These receptors share a characteristic molecular structure of two immunoglobulin-like and two fibronectin type III repeats and have been best characterized for their roles in immune regulation, fertility, thrombosis and phagocytosis. Gas6 and protein S have been identified as ligands for these receptors. Gas6 binding induces tyrosine phosphorylation and downstream signaling pathways that can lead to cell proliferation, migration, or the prevention of apoptosis. Tyro3 and Axl play important regulatory roles in a variety of tissues, including the central nervous, reproductive, immune, and vascular systems. Tyro3 is widely expressed during embryonic development and preferentially expressed during neurogenesis in the central nervous system.