Members of this family interact with erythropoietin (EPO), with subsequent initiation of the downstream chain of events associated with binding of EPO to the receptor, including EPO-induced erythroblast proliferation and differentiation through induction of the JAK2/STAT5 signaling cascade. The domain adopts a secondary structure composed of a short amino-terminal helix, followed by two beta-sandwich regions [1].

1: Efficiency of signalling through cytokine receptors depends critically on receptor orientation. Syed RS, Reid SW, Li C, Cheetham JC, Aoki KH, Liu B, Zhan H, Osslund TD, Chirino AJ, Zhang J, Finer-Moore J, Elliott S, Sitney K, Katz BA, Matthews DJ, Wendoloski JJ, Egrie J, Stroud RM; Nature. 1998;395:511-516. PMID:9774108