Ciliary neurotrophic factor (CNTF)is a trophic protein that promotes survival and/or differentiation of a variety of neuronal cell types including sensory, sympathetic, and motor neurons. CNTF receptor is a three-component complex, the α-subunit is not a transmembrane protein, but is anchored to the membrane via a glycosyl-phosphatidylinositol linkage. The other two components of the receptor complex which participate in the signal transduction are gp130 and LIFRβ. The three components of the receptor are assembled together stepwisely. In the intracellular signal transduction of the receptor, the Jak/Tyk family is involved.