291
In this report we demonstrate that IL-12 induces tyrosine phosphorylation of a recently identified STAT family member , STAT4 , and show that STAT4 expression is regulated by T-cell activation .
 ( protein: STAT family member, None) , ( protein: STAT4, None) , ( protein: STAT4, None) , ( protein: IL-12, 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: STAT family member, None) , ( protein: STAT4, None) , ( protein: STAT4, None) , ( protein: IL-12, None) 