7687
Most erythroleukemic cell lines established in vitro coexpress erythrocytic and megakaryocytic markers that often are associated with expression of Spi-1 and/or Fli-1 transcription factors known as transactivators of megakaryocyte-specific promoters .
 ( protein: Fli-1, None) , ( protein: transactivators of megakaryocyte-specific promoters, None) , ( protein: Spi-1, None) , ( protein: Fli-1 transcription factors, None) , ( DNA: megakaryocyte-specific promoters, None) , ( cell line: erythroleukemic cell lines, 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: Fli-1, None) , ( protein: transactivators of megakaryocyte-specific promoters, None) , ( protein: Spi-1, None) , ( protein: Fli-1 transcription factors, None) , ( DNA: megakaryocyte-specific promoters, None) , ( cell line: erythroleukemic cell lines, None) 