7724
Transfectants grown in the presence of tetracycline contained about 15,000 receptors/cell, a value approximately equal to basal level GR expression in glucocorticoid-sensitive 6TG1.1 cells before steroid treatment .
 ( protein: GR, None) , ( cell line: Transfectants, None) , ( cell line: glucocorticoid-sensitive 6TG1.1 cells, 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: GR, None) , ( cell line: Transfectants, None) , ( cell line: glucocorticoid-sensitive 6TG1.1 cells, None) 