11344
Because binding sites for B-cell-specific activator protein ( BSAP ) are located upstream of several switch regions in the immunoglobulin heavy chain gene cluster , BSAP might play a role in the regulation of germline transcription and isotype switching .
 ( protein: BSAP, None) , ( DNA: immunoglobulin heavy chain gene cluster, None) , ( DNA: binding sites, None) , ( protein: B-cell-specific activator protein, None) , ( protein: BSAP, None) , ( DNA: germline, 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: BSAP, None) , ( DNA: immunoglobulin heavy chain gene cluster, None) , ( DNA: binding sites, None) , ( protein: B-cell-specific activator protein, None) , ( protein: BSAP, None) , ( DNA: germline, None) 