14908
Studies with 5' deletion CD20 promoter-CAT constructs have previously revealed two regions of the promoter between bases -186 and -280 and between bases -280 and -454 which contained positive regulatory elements .
 ( DNA: promoter, None) , ( DNA: positive regulatory elements, None) , ( DNA: 5#$%# deletion CD20 promoter-CAT constructs, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( DNA: promoter, None) , ( DNA: positive regulatory elements, None) , ( DNA: 5#$%# deletion CD20 promoter-CAT constructs, None) 