1375
In this study we demonstrate that a subfragment (C26) in the region between the 21-bp elements is involved in trans-activation by p40tax , possibly through binding to an NF-kappa B -like nuclear factor or factors.
 DNA: 21-bp elements; protein: NF-kappa B; protein: NF-kappa B -like nuclear factor; protein: p40tax
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: 21-bp elements; protein: NF-kappa B; protein: NF-kappa B -like nuclear factor; protein: p40tax