127
Coexpression of alpha B1 and alpha B2 showed that the promoter activity could be determined by the alpha B1 /alpha B2 ratio .
 ( protein: alpha B1, None) , ( protein: alpha B1, None) , ( protein: /alpha B2, None) , ( protein: alpha B2, 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: alpha B1, None) , ( protein: alpha B1, None) , ( protein: /alpha B2, None) , ( protein: alpha B2, None) 