Structural and functional characterisation of recombinant human erythropoietin analogues

AbstractDeletion mutants of a synthetic human erythropoietin-cDNA were transiently expressed in COS-7 cells and products analyzed using Western blots and a cell proliferation assay. Only two mutants with deletions affecting the N-terminal portion and the amino acid sequence 115-121 displayed biological activity. The exchange of hydrophilic, charged amino acids by alanine in two potential α-helical regions, the internal amino acid sequence 102–106 and the C-terminal sequence 154–159, causes a 2–11-fold loss of activity. The results suggest that both regions are involved in either maintaining the active structure of the hormone or interacting with the receptor