Complex of Human EPOR, also known as Erythropoietin receptor, GenBank Accession No. NM_000121, a.a. 273-338 with N-terminal His-tag, MW=9 kDa, and JAK2, also known as Janus Kinase 2, with V617F, Y1007F and Y1008F mutations, GenBank Accession No. NM_004972, a.a. 36-1132(end), with N-terminal FLAG-tag, MW=128 kDa. The proteins were expressed as single fusion protein with a (GSSG)₆ linker in a Baculovirus infected Sf9 cell expression system.