5046
Analysis of different CREB mutants with this genetic system indicated that the C-terminal 92 amino acid residues , which include the basic domain and the leucine zipper , are necessary and sufficient to mediate transactivation by Tax .
 CREB mutants, C-terminal 92 amino acid residues, basic domain, leucine zipper, Tax
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 CREB mutants, C-terminal 92 amino acid residues, basic domain, leucine zipper, Tax