CRLF2 is cytokine receptor-like factor 2. Cytokine signals are mediated through specific receptor complexes, the components of which are mostly members of the type I cytokine receptor family. Type I cytokine receptors share conserved structural features in their extracellular domain. Receptor complexes are typically heterodimeric, consisting of alpha chains, which provide ligand specificity, and beta (or gamma) chains, which are required for the formation of high-affinity binding sites and signal transduction.