6992
Mutation of the E box abolished USF/c-Myc -mediated up-regulation of CXCR4 promoter activity , and mutation of the YY1 binding site was associated with unresponsiveness to YY1 -mediated inhibition .
 ( protein: USF/c-Myc, None) , ( DNA: YY1 binding site, None) , ( protein: CXCR4, None) , ( DNA: E box, None) , ( protein: YY1, None) , ( protein: YY1, 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: USF/c-Myc, None) , ( DNA: YY1 binding site, None) , ( protein: CXCR4, None) , ( DNA: E box, None) , ( protein: YY1, None) , ( protein: YY1, None) 