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Since HIV-1 long terminal repeat contains two functional nuclear factor kB ( NF-kB ) regulatory elements , we studied the ability of PMA to induce NF-kB binding activity by different assays.
 DNA: HIV-1 long terminal repeat; protein: NF-kB; protein: NF-kB; DNA: nuclear factor kB ( NF-kB ) regulatory elements
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 DNA: HIV-1 long terminal repeat; protein: NF-kB; protein: NF-kB; DNA: nuclear factor kB ( NF-kB ) regulatory elements