Ciliary neurotrophic factor receptor subunit alpha (CNTFR or CNTFR-alpha) belongs to the type I cytokine receptor family and type 3 subfamily. CNTFR contains two fibronectin type-III domains and one Ig-like C2-type (immunoglobulin-like) domain. This receptor and its cognate ligand support the survival of neurons. This receptor is most closely related to the interleukin-6 receptor. This receptor possesses an unusual attachment to the cell membrane through a glycophosphatidylinositol linkage.