6986
USF/c-Myc enhances, while Yin-Yang 1 suppresses, the promoter activity of CXCR4 , a coreceptor for HIV-1 entry .
 ( protein: coreceptor, None) , ( protein: USF/c-Myc, None) , ( protein: CXCR4, None) , ( protein: Yin-Yang 1, 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: coreceptor, None) , ( protein: USF/c-Myc, None) , ( protein: CXCR4, None) , ( protein: Yin-Yang 1, None) 