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Two major protein-binding sites within the negative regulatory element of the human immunodeficiency virus type 1 long terminal repeat have been identified.
 DNA: human immunodeficiency virus type 1 long terminal repeat; DNA: negative regulatory element; DNA: major protein-binding sites
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: human immunodeficiency virus type 1 long terminal repeat; DNA: negative regulatory element; DNA: major protein-binding sites