13474
In contrast, deletion of the upstream portion of the delta promoter led to a 10 fold decrease in expression.
 ( DNA: delta promoter, None) , ( DNA: upstream portion, 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: delta promoter, None) , ( DNA: upstream portion, None) 