3320
In addition Spi-B as well as PU.1 were able to transactivate Btk expression .
 ( protein: PU.1, None) , ( protein: Btk, None) , ( protein: Spi-B, 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: PU.1, None) , ( protein: Btk, None) , ( protein: Spi-B, None) 