4539
In addition to the already identified NIP repressor site , evidence is presented for a second repressor region that restricts promoter activity in fibroblasts .
 ( cell type: fibroblasts, None) , ( DNA: NIP repressor site, None) , ( DNA: second repressor region, 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:
 ( cell type: fibroblasts, None) , ( DNA: NIP repressor site, None) , ( DNA: second repressor region, None) 