4078
When single-point mutation was introduced to each GC box , EBS , and GT box in PFP9a20 , at least 3-fold less CAT activity was observed in CTLL-R8 cells .
 ( DNA: EBS, None) , ( DNA: PFP9a20, None) , ( DNA: GC box, None) , ( protein: CAT, None) , ( cell line: CTLL-R8 cells, None) , ( DNA: GT box, 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: EBS, None) , ( DNA: PFP9a20, None) , ( DNA: GC box, None) , ( protein: CAT, None) , ( cell line: CTLL-R8 cells, None) , ( DNA: GT box, None) 