5061
To investigate the regulation of IL-13 gene expression by T cells , we isolated and sequenced the human IL-13 gene , analyzed its 5'-flanking region for potential transcriptional activation elements , and examined its expression in nontransformed T-lineage cell populations .
 ( cell type: T cells, None) , ( cell line: nontransformed T-lineage cell populations, None) , ( DNA: IL-13 gene, None) , ( DNA: transcriptional activation elements, None) , ( protein: IL-13, None) , ( protein: IL-13, None) , ( DNA: 5#$%#-flanking region, None) , ( DNA: IL-13 gene, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( cell type: T cells, None) , ( cell line: nontransformed T-lineage cell populations, None) , ( DNA: IL-13 gene, None) , ( DNA: transcriptional activation elements, None) , ( protein: IL-13, None) , ( protein: IL-13, None) , ( DNA: 5#$%#-flanking region, None) , ( DNA: IL-13 gene, None) 