2058
Human immunodeficiency virus type 1 ( HIV-1 ) negative factor ( Nef ) has been shown to down-regulate the transcription factors NF-kappa B and AP-1 in vitro.
 ( protein: negative factor, None) , ( protein: transcription factors, None) , ( protein: AP-1, None) , ( protein: Nef, None) , ( protein: NF-kappa B, 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: negative factor, None) , ( protein: transcription factors, None) , ( protein: AP-1, None) , ( protein: Nef, None) , ( protein: NF-kappa B, None) 