13867
Tyrosine phosphorylation STAT1 or STAT3 was not detected in human erythroid precursors after stimulation with erythropoietin .
 ( protein: STAT1, None) , ( cell type: human erythroid precursors, None) , ( protein: erythropoietin, None) , ( protein: STAT3, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( protein: STAT1, None) , ( cell type: human erythroid precursors, None) , ( protein: erythropoietin, None) , ( protein: STAT3, None) 