Identification of protein phosphatase 2A as the major tyrosine hydroxylase phosphatase in adrenal medulla and corpus striatum: evidence from the effects of okadaic acid

Jan Haavik, Donald L. Schelling, David G. Campbell, Kristoffer K. Andersson, Torgeir Flatmark, Philip Cohen

Research output: Contribution to journalArticle

88 Citations (Scopus)

Abstract

(i) The major sites on bovine adrenal tyrosine hydroxylase (TH) phosphorylated by calmodulin-dependent multiprotein kinase (CaM-MPK) and cyclic AMP-dependent protein kinase were shown to be Ser-19 and Ser-40, respectively, while Ser-40 was also phosphorylated slowly by CAM-MPK. (ii) Type 2A and type 2C phosphatases accounted for ≈90% and ≈ 10% of TH phosphatase activity, respectively, in extracts of adrenal medulla and corpus striatum assayed at near physiological free Mg2+(1 mM), while type 1 and type 2B phosphatases had negligible activity towards TH. (iii) Incubation of adrenal chromaffin cells with okadaic acid increased TH phosphorylation by 206% and activity by 77%, establishing that type 2A phosphatases play a major role in regulating TH in vivo.

Original languageEnglish
Pages (from-to)36-42
Number of pages7
JournalFEBS Letters
Volume251
Issue number1-2
DOIs
Publication statusPublished - 17 Jul 1989

Keywords

  • Calmodulin
  • cyclic AMP
  • Okadaic acid
  • Protein kinase
  • Protein phosphatase
  • Protein sequencing
  • Tyrosine hydroxylase

Fingerprint Dive into the research topics of 'Identification of protein phosphatase 2A as the major tyrosine hydroxylase phosphatase in adrenal medulla and corpus striatum: evidence from the effects of okadaic acid'. Together they form a unique fingerprint.

  • Cite this