14700
These data suggest that transcriptional activation of human embryonic zeta 2 globin gene and the fetal/adult alpha globin genes is mediated by erythroid cell-specific and developmental stage-specific nuclear factor-DNA complexes which form at the enhancer ( HS-40 ) and the globin promoters .
 ( protein: nuclear factor-DNA complexes, None) , ( DNA: HS-40, None) , ( DNA: enhancer, None) , ( DNA: fetal/adult alpha globin genes, None) , ( DNA: human embryonic zeta 2 globin gene, None) , ( protein: developmental stage-specific nuclear factor-DNA complexes, None) , ( DNA: zeta 2 globin gene, None) , ( DNA: globin promoters, 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: nuclear factor-DNA complexes, None) , ( DNA: HS-40, None) , ( DNA: enhancer, None) , ( DNA: fetal/adult alpha globin genes, None) , ( DNA: human embryonic zeta 2 globin gene, None) , ( protein: developmental stage-specific nuclear factor-DNA complexes, None) , ( DNA: zeta 2 globin gene, None) , ( DNA: globin promoters, None) 