2170
To examine whether the AP-1 enhancer activity is involved in RA -induced monocytic differentiation , THP-1 cells were transiently transfected with a chloramphenicol acetyl transferase ( CAT )-reporter gene containing 5 copies of the AP-1 binding sites .
 ( protein: chloramphenicol acetyl transferase, None) , ( protein: AP-1, None) , ( DNA: chloramphenicol acetyl transferase ( CAT )-reporter gene, None) , ( DNA: AP-1 binding sites, None) , ( cell line: THP-1 cells, None) , ( protein: CAT, None) , ( DNA: AP-1 enhancer, 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: chloramphenicol acetyl transferase, None) , ( protein: AP-1, None) , ( DNA: chloramphenicol acetyl transferase ( CAT )-reporter gene, None) , ( DNA: AP-1 binding sites, None) , ( cell line: THP-1 cells, None) , ( protein: CAT, None) , ( DNA: AP-1 enhancer, None) 