1916
Since these findings supported the involvement of serine /threonine protein phosphorylation in the regulation of EGR-1 expression , we studied activation of the 40S ribosomal protein S6 serine /threonine kinases , pp70S6K and pp90rsk .
 ( protein: pp70S6K, None) , ( protein: pp90rsk, None) , ( protein: 40S ribosomal protein S6 serine /threonine kinases, None) , ( DNA: EGR-1, 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: pp70S6K, None) , ( protein: pp90rsk, None) , ( protein: 40S ribosomal protein S6 serine /threonine kinases, None) , ( DNA: EGR-1, None) 