12925
Activation of the CD4 promoter occurs in the presence of the viral DNA polymerase inhibitor phosphonoformic acid , which limits expression to the immediate-early and early classes of viral genes .
 ( DNA: CD4 promoter, 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: CD4 promoter, None) 