11894
A dominant-negative mutant of NF-kappaB p50 that binds DNA but fails to interact with Ets proteins inhibits the synergistic activation of the HIV-1 and HIV-2 enhancers by NF-kappaB ( p50 + p65 ) and Ets-1 , suggesting that physical interaction between Ets and NF-kappaB proteins is required for the transcriptional activity of the HIV-1 and HIV-2 enhancers .
 ( protein: NF-kappaB, None) , ( protein: NF-kappaB p50, None) , ( protein: p65, None) , ( protein: Ets proteins, None) , ( protein: NF-kappaB, None) , ( protein: NF-kappaB proteins, None) , ( protein: p50, None) , ( protein: Ets, None) , ( protein: Ets-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: NF-kappaB, None) , ( protein: NF-kappaB p50, None) , ( protein: p65, None) , ( protein: Ets proteins, None) , ( protein: NF-kappaB, None) , ( protein: NF-kappaB proteins, None) , ( protein: p50, None) , ( protein: Ets, None) , ( protein: Ets-1, None) 