11334
To investigate the mechanisms responsible for tissue-specific expression of the IL-4 gene, we analyzed nuclear factors binding to the PRE-I site and compared the binding activities of these factors to the IL-4 promoter of Th1 and Th2 cells .
 ( protein: IL-4, None) , ( protein: IL-4, None) , ( DNA: PRE-I site, None) , ( protein: nuclear factors, 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: IL-4, None) , ( protein: IL-4, None) , ( DNA: PRE-I site, None) , ( protein: nuclear factors, None) 