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Cell culture experiments demonstrated that the natural variant with four Sp1 sites had a slightly higher promoter activity and viral replication rate than the isogenic control LTR with three Sp1 sites .
 protein: Sp1; DNA: isogenic control LTR; DNA: Sp1 sites; protein: Sp1; DNA: Sp1 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:
 protein: Sp1; DNA: isogenic control LTR; DNA: Sp1 sites; protein: Sp1; DNA: Sp1 sites