14690
It was shown by transient expression assay that HS-40 behaved as an authentic enhancer for high-level zeta 2 globin promoter activity in K562 cells , an erythroid cell line of embryonic and/or fetal origin.
 ( DNA: enhancer, None) , ( DNA: HS-40, None) , ( cell line: K562 cells, None) , ( DNA: zeta 2 globin promoter, 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:
 ( DNA: enhancer, None) , ( DNA: HS-40, None) , ( cell line: K562 cells, None) , ( DNA: zeta 2 globin promoter, None) 