3723
All cells tested express TAFII105 mRNA , but only B cells contain significant levels of protein associated with TFIID .
 ( cell type: B cells, None) , ( protein: TFIID, None) , ( RNA: TAFII105 mRNA, 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: B cells, None) , ( protein: TFIID, None) , ( RNA: TAFII105 mRNA, None) 