4433
Gel mobility shift and immunoprecipitation analyses revealed that in addition to activating STAT3 ( signal transducer and activator of transcription-3 ) and STAT5 , IL-2 induced tyrosine and serine phosphorylation of STAT1 alpha , which formed IFN-gamma-activated sequence-binding complexes by itself and with STAT3 .
 ( protein: STAT3, None) , ( protein: IFN-gamma-activated sequence-binding complexes, None) , ( protein: signal transducer and activator of transcription-3, None) , ( protein: STAT1 alpha, None) , ( protein: STAT3, None) , ( protein: IL-2, None) , ( protein: STAT5, 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: STAT3, None) , ( protein: IFN-gamma-activated sequence-binding complexes, None) , ( protein: signal transducer and activator of transcription-3, None) , ( protein: STAT1 alpha, None) , ( protein: STAT3, None) , ( protein: IL-2, None) , ( protein: STAT5, None) 