12303
Phosphorylation of CREB occurred through a herbimycin A and Rp-cAMP- sensitive pathway , suggesting phosphorylation required antecedent activation of both protein tyrosine kinases ( PTK ) and protein kinase A ( PKA ).
 ( protein: CREB, None) , ( protein: PKA, None) , ( protein: protein tyrosine kinases, None) , ( protein: PTK, None) , ( protein: protein kinase A, 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: CREB, None) , ( protein: PKA, None) , ( protein: protein tyrosine kinases, None) , ( protein: PTK, None) , ( protein: protein kinase A, None) 