Tyrosine hydroxylase: Studies on the phosphorylation of a purified preparation of the brain enzyme by the cyclic AMP-dependent protein kinase Academic Article uri icon


MeSH Major

  • Brain
  • Protein Kinases
  • Tyrosine 3-Monooxygenase


  • Tyrosine hydroxylase [L-tyrosine, tetrahydropteridine: oxygen oxidoreductase (3-hydroxylating); EC](TH) was purified from bovine corpus striatum. The purification involved sequential DEAE cellulose, hydroxylapatite and CM Sephadex C-50 chromatography, followed by glycerol density gradient centrifugation. Final preparations appeared to be 90 to 100% pure as judged by polyacrylamide gel electrophoresis under denaturing conditions in acetic acid-urea. The enzyme was estimated to have a minimum molecular weight of approximately 60,000 daltons. Purified TH could be activated in vitro by incubation with magnesium adenosine triphosphate and the catalytic subunit of cyclic AMP-dependent protein kinase (ATP/protein phosphotransferase; EC When the final purified preparation of TH was incubated under these conditions utilizing [gamma-32P]ATP, it was found to incorporate 0.7 to 0.9 mol of phosphorus/mol of protein. These results suggest that the activation of TH in the presence of phosphorylating conditions is due to its phosphorylation by cyclic AMP-dependent protein kinase.

publication date

  • January 1981



  • Academic Article



  • eng

PubMed ID

  • 6110771

Additional Document Info

start page

  • 647

end page

  • 53


  • 216


  • 3