7421
In the cytoplasm it acts as a dehydratase in the regeneration of tetrahydrobiopterin , the cofactor for aromatic amino acid hydroxylases .
 ( protein: aromatic amino acid hydroxylases, None) , ( protein: dehydratase, None) , ( protein: tetrahydrobiopterin, 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: aromatic amino acid hydroxylases, None) , ( protein: dehydratase, None) , ( protein: tetrahydrobiopterin, None) 