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IL-2 responsiveness , on the other hand, depends on a 78-nucleotide segment 1.3 kilobases upstream of the major transcription start site .
 major transcription start site, IL-2, 78-nucleotide segment
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:
 major transcription start site, IL-2, 78-nucleotide segment