10190
In addition, in vivo footprint analysis showed the putative X and Y boxes to be occupied by transcription factors in wild-type B cells , but not in RFX -deficient B cells .
 ( cell type: wild-type B cells, None) , ( cell type: B cells, None) , ( cell line: RFX -deficient B cells, None) , ( protein: transcription factors, None) , ( protein: RFX, 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:
 ( cell type: wild-type B cells, None) , ( cell type: B cells, None) , ( cell line: RFX -deficient B cells, None) , ( protein: transcription factors, None) , ( protein: RFX, None) 