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; protein: PKA; protein: protein tyrosine kinases; protein: PTK; protein: protein kinase A
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
 Entities: CREB, PKA, protein tyrosine kinases, PTK, protein kinase A 
Answer:
 protein: CREB; protein: PKA; protein: protein tyrosine kinases; protein: PTK; protein: protein kinase A