erythropoietin , purified to apparent homogeneity and freed of trace contamination by endotoxin ( 1 ) promotes erythroid burst formation from mouse marrow cells in semi-solid culture medium , ( 2 ) stimulates haemoglobin synthesis in rat marrow cell cultures , ( 3 ) stimulates transcription in mouse and rat bone marrow cell cultures and ( 4 ) causes the formation of the cytoplasmic mediator protein in rat marrow cells , which enhances transcription in isolated nuclei .
C0010834
cytoplasmic
C0007634
cells