2851
The sequence between -1.7 and -0.2 kb linked to a heterologous thymidine kinase promoter failed to respond to PRL stimulation, suggesting that the activity of upstream PRL response elements may require an interaction with promoter-proximal elements .
 ( protein: PRL, None) , ( DNA: heterologous thymidine kinase promoter, None) , ( DNA: upstream PRL response elements, None) , ( DNA: promoter-proximal elements, None) , ( protein: PRL, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( protein: PRL, None) , ( DNA: heterologous thymidine kinase promoter, None) , ( DNA: upstream PRL response elements, None) , ( DNA: promoter-proximal elements, None) , ( protein: PRL, None) 