Distribution of protein phosphatase inhibitor-1 in brain and peripheral tissues of various species: comparison with DARPP-32

J Neurochem. 1992 Sep;59(3):1053-61. doi: 10.1111/j.1471-4159.1992.tb08347.x.


The distribution of inhibitor-1, a cyclic AMP-regulated inhibitor of protein phosphatase-1, was analyzed in various brain regions and peripheral tissues of various species by immunolabeling of sodium dodecyl sulfate-poly-acrylamide gel transfers using specific antibodies. The distribution of inhibitor-1 was directly compared to that of DARPP-32, a structurally related cyclic AMP-regulated inhibitor of protein phosphatase-1. In rat CNS, a single immunoreactive protein of M(r) 30,000, identified as inhibitor-1, was widely distributed. In contrast, DARPP-32 was highly concentrated in the basal ganglia. Inhibitor-1 was detected in brain tissue from frog (M(r) 27,000), turtle (M(r) 29,000/33,000), canary (M(r) 26,000), pigeon (M(r) 28,000), mouse (M(r) 30,500), rabbit (M(r) 26,500), cow (M(r) 27,000), and monkey (M(r) 27,500), but not from goldfish. Inhibitor-1 was detected at various levels in most peripheral tissues of the species studied; however, it was not detectable in certain tissues of particular species (e.g., rat and cow liver). DARPP-32 was detected in brain tissue of all the species tested except frog and goldfish, but was not detectable in most peripheral tissues. Both inhibitor-1 and DARPP-32 were concentrated in the cytosol and synaptosomal cytosol of rat striatum. The developmental expressions of inhibitor-1 and DARPP-32 in rat striatum differed: the level of inhibitor-1 peaked in the first postnatal week and then declined by the third postnatal week, whereas the level of DARPP-32 increased to a peak level by the third postnatal week and remained elevated thereafter.(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Brain / metabolism*
  • Brain / ultrastructure
  • Carrier Proteins*
  • Central Nervous System / metabolism
  • Dopamine and cAMP-Regulated Phosphoprotein 32
  • Enzyme Inhibitors / metabolism
  • Female
  • Intracellular Signaling Peptides and Proteins*
  • Male
  • Nerve Tissue Proteins / metabolism*
  • Phosphoproteins / metabolism
  • Proteins / metabolism*
  • Rats / metabolism
  • Rats, Inbred Strains
  • Subcellular Fractions / metabolism
  • Tissue Distribution
  • Tyrosine 3-Monooxygenase / metabolism
  • Vertebrates / metabolism


  • Carrier Proteins
  • Dopamine and cAMP-Regulated Phosphoprotein 32
  • Enzyme Inhibitors
  • Intracellular Signaling Peptides and Proteins
  • Nerve Tissue Proteins
  • Phosphoproteins
  • Proteins
  • protein phosphatase inhibitor-1
  • Tyrosine 3-Monooxygenase