819
Mutations in this DNA-binding site abolished binding of a nuclear factor in human B cell nuclear extract and decreased the activity of the DR alpha promoter to a basal level .
 ( protein: nuclear factor, None) , ( DNA: DNA-binding site, None) , ( DNA: DR alpha 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:
 ( protein: nuclear factor, None) , ( DNA: DNA-binding site, None) , ( DNA: DR alpha promoter, None) 