4131
The previously defined minimal enhancer containing the muA , muE3 , and muB sites is transactivated by a combination of the ETS-domain proteins PU.1 and Ets-1 in nonlymphoid cells .
 PU.1, Ets-1, ETS-domain proteins, nonlymphoid cells, minimal enhancer
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:
 PU.1, Ets-1, ETS-domain proteins, nonlymphoid cells, minimal enhancer