4972
Electrophoretic mobility shift analyses demonstrated that the 151-bp region contains nuclear protein binding sites for Sp1 , PU.1 , and/or Elf-1 , and a novel factor .
 nuclear protein binding sites, novel factor, PU.1, Elf-1, Sp1, 151-bp region
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:
 nuclear protein binding sites, novel factor, PU.1, Elf-1, Sp1, 151-bp region