14918
Together these results suggest that the BAT box binding proteins are important in the B cell specific expression of CD20 and perhaps CD21 .
 ( protein: CD20, None) , ( protein: BAT box binding proteins, None) , ( protein: CD21, 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: CD20, None) , ( protein: BAT box binding proteins, None) , ( protein: CD21, None) 