7036
Upon TPA treatment , the activity of ERK1 and ERK2 rapidly increased, with maximal induction between 1 and 3 h, while ERK2 protein levels remained constant.
 ( protein: ERK2, None) , ( protein: ERK1, None) , ( protein: ERK2, 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: ERK2, None) , ( protein: ERK1, None) , ( protein: ERK2, None) 