1546
DNA binding by all four of these Rel-related factors is blocked by selective chemical modification of lysine and arginine residues , suggesting that both of these basic amino acids are required for binding to the kappa B element .
 protein: Rel-related factors; DNA: kappa B element
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: Rel-related factors; DNA: kappa B element